Digital Heater Element Burnout Detector
K8AC-H
A high-precision Heater Element
Burnout Detector compatible with a
wide-range of heater control methods.
• Push-in terminals reduce the workload. *1
• Scaling *1
• NPN or PNP equivalent output. *1
• Lineup includes models compatible with many heater control methods,
including ON/OFF control, phase control, and cyclic control.
• High-precision heater burnout alarm with digital measurement.
• Contributes to preventative maintenance.
• If the gate function is disabled, the gate input can be used as an
undercurrent/overcurrent relay or for motor or lamp loads.
• Undercurrent detection values can be set separately for CT1 and
CT2. *2
• CE marking and cUL certified (K8AC-H2@@@).
*1. K8AC-H2@@@ Series only.
*2. The overvoltage detection value is the same for the CT1 and CT2. Also, there
is one undercurrent output. Wide Current Input Range: 0.200 to 200.0 A AC.
Note: 1. Consult with your OMRON representative before using the K8AC with
phase control or cyclic control under the following conditions. For the most recent information on models that have been certified for
• Using multiple heaters with different heater capacities safety standards, refer to your OMRON website.
• Using heaters with varying heater resistance (e.g., halogen heaters)
2. The K8AC-H is designed to monitor for element burnouts on heaters
controlled with power regulators that used a three-alarm method.
Normal monitoring is not possible for circuits that use a power regulator with a six-alarm method.
Features
High-precision Heater Burnout Alarms with Push-in Terminals for Reduced Wiring Work
High-resolution Digital Measurement (K8AC-H2@@@ Series Only)
Burnout Alarm Possible for One of Multiple Push-in terminals have no screws to come loose, which eliminates
Heater Elements the need to control screw tightening torque and retighten screws and
helps to reduce your workload.
Heater burnout is detected by digitally processing minor current
fluctuations.
RST E5@@
Digital
Temperature
G3PE Controller
Three-phase
SSR Easily connect terminals using ferrules with insulation sleeves.
Easy Scaling Using the External CT Ratio
and Number of CT Passes
(K8AC-H2@@@ Series Only)
Current Transformer Easily set the scaling just by inputting (1) the CT ratio and (2) the
K8AC-H@ number of CT passes.
Digital Heater External
Element Burnout CT
Detector
Electric @A/1A
oven (1) CT ratio K8AC-CT@
Three-phase Current Transformer
delta-connected heater
(2) Number of CT passes
Heater
1
K8AC-H
Compatible with Various Heater Control The transistor output from the K8AC-H2@@N
Methods can be used as either an NPN open-collector
Models with heater burnout alarms for ON/OFF control, phase output or a PNP equivalent output.
control, and cyclic control have been added to the lineup. The transistor output of the K8AC-H2@@N uses a photocoupler for
Check the current input range, connected CT, and relay output type isolation with the internal circuits, and so either an NPN open-
before selecting the model from the product specifications. collector output or a PNP equivalent output can be used.
Note: Both single-phase and three-phase heaters are supported.
NPN Output PNP Equivalent Output
Overcurrent and SSR Failure Detection from
Heater Layer Short Circuits.
• Overcurrent can be detected from layer short circuits in addition to
providing heater burnout alarms with overcurrent detection
settings. Load Load
• SSR short circuit failures and SSR open circuit failures are
detected by monitoring the heater current and the control outputs Load power supply Load power supply
from the temperature controller.
• Detecting SSR failures enables promptly discovering that Preventive Maintenance
temperature control has failed. The run time can be measured by the K8AC-H.
Heater Burnout Alarms for Cyclic Control or Managing the run time history until burnouts occur is useful for
Phase Control Heaters diagnosis and preventative maintenance for equipment.
(K8AC-H@@P@) Count the Total Number of Alarms Output
The burnout detection value is shifted according to the Set the upper and lower limits to count the total number of alarms that
control output value from the temperature controller. have been output.
• Analog control is performed on the output power according to the
temperature controller's current output (4 to 20 mA) when phase
control or cyclic control is used.
• Heater burnout alarms are stable with the K8AC-H because the
heater burnout alarm values are linked with the control output
value from the temperature controller.
Heater current Heater current
Heater Burnout Alarm Value
The heater burnout alarm value shifts
according to the control input (4 to
Heater burnout 20 mA) from the temperature controller.
alarm value
4 mA 7 mA 20 mA
Control output from temperature controller
Compatible with Gradient Settings of Power Controllers
When using gradient settings with a power controller, set a gate
current level that is suitable for the gradient settings.
Output current
100% Measurement range Gradient setting: 100%
Gradient setting: 50%
0% Control signal
4 mA 14 mA 20 mA
Not detected Detected
Operation gate current level
Note: Set the heater burnout alarm value based on the current at the
heater's rated input.
2
K8AC-H
Model Number Structure
Model Number Legend
K8AC-H@@@@ -FLK 100-240VAC
1 2 3 4 5 6 7
1. Basic Model 5. Output Type
K8AC-H: Digital Heater Element Burnout Detector C: Contact output (one SPDT relay contact output)
2. Product Type T: Transistor output (two NPN open collector outputs) *1
1: Screw terminals N: Transistor outputs (Two outputs: either NPN open-collector
2: Push-in terminals (Power Input: Screw Terminals.) output or PNP equivalent output can be used.) *2
3. Current Input Range *1. K8AC-H1@@T only.
*2. K8AC-H2@@N only.
1: 0.200 to 2.200 A 6. Communications Specifications
2: 2.00 to 22.00 A FLK: RS-485
3: 20.0 to 200.0 A 7. Power Supply Voltage
4. Heater Control Type 100-240VAC: 100 to 240 VAC
C:ON/OFF control (SSR or contactor)
P: Phase control or cyclic control
Ordering Information
Digital Heater Element Burnout Detectors
Models with Push-in Terminals (Power Input: Screw Terminals)
Power Input Com- Current input range
supply Heater control specifica- Output specifi- munica-
voltage method tions cations tions 0.200 to 2.200 A 2.00 to 22.00 A 20.0 to 200.0 A
output
ON/OFF control Two One relay output K8AC-H21CC-FLK K8AC-H22CC-FLK K8AC-H23CC-FLK
SSR control current Two transistor
inputs outputs K8AC-H21CN-FLK K8AC-H22CN-FLK K8AC-H23CN-FLK
100 to (for either RS-485
240 VAC single- One relay output K8AC-H21PC-FLK K8AC-H22PC-FLK K8AC-H23PC-FLK
Phase control phase or Two transistor
Cyclic control three- outputs K8AC-H21PN-FLK K8AC-H22PN-FLK K8AC-H23PN-FLK
phase)
K8AC-CT200 or Current
Applicable Current Transformer K8AC-CT20S or K8AC-CT20L K8AC-CT200L Transformers
(sold separately)
Note: Consult with an OMRON representative if multiple heaters with different capacities are to be connected in parallel or if the heater resistance
will vary.
Models with Screw Terminals Production To Be Discontinued at the End of March 2009
Power Input Com- Current input range
supply Heater control specifica- Output specifi- munica-
voltage method tions cations tions 0.200 to 2.200 A 2.00 to 22.00 A 20.0 to 200.0 A
output
ON/OFF control Two One relay output K8AC-H11CC-FLK K8AC-H12CC-FLK K8AC-H13CC-FLK
SSR control current Two transistor
inputs outputs K8AC-H11CT-FLK K8AC-H12CT-FLK K8AC-H13CT-FLK
100 to (for either RS-485
240 VAC single- One relay output K8AC-H11PC-FLK K8AC-H12PC-FLK K8AC-H13PC-FLK
Phase control phase or Two transistor
Cyclic control three- outputs K8AC-H11PT-FLK K8AC-H12PT-FLK K8AC-H13PT-FLK
phase)
K8AC-CT200 or Current
Applicable Current Transformer K8AC-CT20S or K8AC-CT20L K8AC-CT200L Transformers
(sold separately)
Note: Consult with an OMRON representative if multiple heaters with different capacities are to be connected in parallel or if the heater resistance
will vary.
Optional Products (Sold Separately)
Current Transformers
Through-hole diameter Rated current Installation method Model
5.8-mm dia. Surface-mounted with screws K8AC-CT20S
0.200 to 22.00 A Rear-surface mounted with screws K8AC-CT20L
12-mm dia. Binding band
20.0 to 200.0 A Rear-surface mounted with screws K8AC-CT200
Binding band
30-mm dia. 20.0 to 200.0 A Surface-mounted with screws K8AC-CT200L
Note: When selecting a Current Transformer, make sure that the rated current of the heater does not exceed the rated upper limit or the rated
current of the Current Transformer.
3
K8AC-H
Specifications
Ratings
Heater control method Models for ON/OFF control (e.g., SSRs or contactors) Models for phase control and cyclic control
Item Model K8AC-H@@C@-FLK K8AC-H@@P@-FLK
Power supply voltage 100 to 240 VAC (50/60 Hz) *2
Operating voltage range 85% to 110% min. of the rated power supply voltage (85 to 264 V)
Power consumption 35 VA max.
(at max. load)
Applicable circuits Single-phase or three-phase (with same model)
ON/OFF control (e.g., temperature controller with relay output)
Applicable control methods SSR control (e.g., temperature controller with voltage output)
Cyclic control and phase control (e.g., temperature controller with current output)
Current measurement via two special Current Transformers (Burnout alarm set value can be set separately for each Current
Input signal and applicable Current Transformer.)
Transformer Refer to Current Measurement Ranges by Model on page 6 for information on the current measurement range and
applicable Current Transformer.
Measurement method Average value calculation
ON/OFF control Voltage = 12/24 VDC (continuous input possible to 30 VDC) ---
Input impedance = 4 kΩ min.
ON voltage: 9.6 VDC max., OFF voltage: 1 VDC min.
Gate input SSR control Minimum voltage pulse ON time for burnout detection: ---
signal *1 200 ms min.
Input impedance = 4 kΩ min.
Cyclic and phase con- 4 to 20 mA DC (Burnout detection is possible for an input of
trol --- 7 mA or greater.)
Input impedance = 50 Ω max.
One SPDT relay contact output
Relay contact outputs: Same output used for heater burnout, SSR short circuit, SSR open circuit, and heater layer short circuit alarms.
K8AC-H@@@C-FLK 0.3 A at 125 VAC (resistive load), 1 A at 30 VDC (resistive load)
Maximum switching capacity: 37.5 VA, 30 W
Mechanical durability: 50 million operations min., electrical durability: 100,000 operations min.
Two transistor outputs (NPN open-collector)
Transistor outputs One ALM output: Outputs heater burnout alarm or heater layer short circuit alarm.
Outputs (NPN open-collector): One SSR error output: Outputs SSR short circuit alarm or SSR open circuit alarm.
K8AC-H1@@T-FLK 12 to 24 VDC, 50 mA max.
OFF leakage current: 100 μA max., ON residual voltage: 1.5 V max.
Two transistor outputs: Can be used either NPN open-collector outputs or PNP equivalent outputs.
Transistor outputs: One ALM output: Outputs heater burnout alarm or heater layer short circuit alarm.
K8AC-H2@@N-FLK One SSR error output: Outputs SSR short circuit or SSR open circuit detection.
12 to 24 VDC, 50 mA
OFF leakage current: 100 μA max., ON residual voltage: 1.5 V max.
Communications RS-485 1200, 2400, 4800, 9600, 19200 bps (CompoWay/F)
Indication method 7-segment digital display: No. of display digits: 4 (red)
LED status indicators: RUN (green), ADJ (orange), SET (orange), GATE (orange), SSR (orange) and ALM (orange)
Heater burnout alarm, heater layer short circuit alarm, SSR short circuit detection, SSR open circuit detection, voltage
Main functions fluctuation compensation, output ON-delay timer, energy-saving mode, key protection, and power supply voltage
measurement
Ambient Operating −10 to 55°C (with no icing or condensation)
temperature Storage −25 to 65°C (with no icing or condensation)
Ambient Operating 25% to 85% (with no condensation)
humidity Storage 25% to 85% (with no condensation)
Altitude 2,000 m max.
Accessories Instruction sheet
Case material PC (Polycarbonate)
Case color N1.5 (clear black)
Mounting method Mounting to a DIN Track
*1. The gate input enables correct measurement by syncing to heater control.
When using it with ON/OFF control, receive the relay contact output from the temperature controller or other controller with a 24-VDC auxiliary
relay and then use this signal as the gate input signal to the K8AC.
The gate function can also be disabled. If it is disabled, the gate input can be used as a normal undercurrent/overcurrent relay.
*2. When using the K8AC-H for a 380 to 480-V AC power supply circuit, use a step-down transformer. Contact your OMRON representative for
information on transformers.
*3. Order the Current Transformers separately.
4
K8AC-H
Characteristics
Heater control method Models for ON/OFF control (e.g., SSRs or contactors) Models for phase control and cycle control
Item Model K8AC-H@@@C@-FLK K8AC-H@@P@-FLK
Heater current Input range K8AC-H@1@@: 0.200 to 2.200 A (Current Transformer: K8AC-CT20S (5.8 dia.), K8AC-CT20L (12 dia.) *1)
K8AC-H@2@@: 2.00 to 22.00 A (Current Transformer: K8AC-CT20S (5.8 dia.), K8AC-CT20L (12 dia.) *1)
input K8AC-H@3@@: 20.0 to 200.0 A (Current Transformer: K8AC-CT200 (12 dia.), K8AC-CT200L (30 dia.) *1)
(at 10 to 30°C)
category II Measurement accuracy ±3% rdg ±10 digits max. *2 ±6% rdg ±10 digits max. (at control level of 100%) *2
Voltage Input range 85 to 264 VAC
fluctuation
compensation Measurement accuracy ±3% rdg ±10 digits max.
category II
Gate input Input range 0 to12 VDC or 0 to 24 VDC 4 to 20 mA DC
ON: 9.6 VDC max., OFF: 1 VDC min.
Display cycle Selectable: Immediate, 0.2 s, 0.5 s, 1.0 s
Output ON-delay time 0.0 to 99.9 s (operating time)
Soft start time 0.0 to 99.9 s (used when using the soft start function of a Power Controller)
Output reset method Automatic reset
Alarm hysteresis 1 to 999 digits
Output response time 500 ms max. 3.5 s max.
20 MΩ min.
Between terminals and case
Insulation resistance Between power supply terminals/CT primary terminals and gate input terminals/communications terminals
Between power supply terminals/CT primary terminals and output terminals
Between gate input terminal/communications terminals and output terminals
2,000 V for 1 min
Dielectric strength Between terminals and case
Between power supply terminals/CT primary terminals and gate input terminals/communications terminals
Between power supply terminals/CT primary terminals and output terminals
Between gate input terminal/communications terminals and output terminals
Noise immunity Power supply terminals normal/common mode: ±1,500 V (startup 1-ns square-wave noise, pulse width: 1 μs/100 ns)
Vibration resistance Vibration: 10 to 55 Hz, Acceleration: 50 m/s2 for 5 min with 10 sweeps each in X, Y, and Z directions
Shock resistance 150 m/s2 (100 m/s2 for relay contacts) 3 times in 6 directions in X, Y, and Z directions
Current Transformer K8AC-H@1@@: 4 A: 30 s, 12 A: 1 s
K8AC-H@2@@: 40 A: 30 s, 120 A: 1 s
primary current K8AC-H@3@@: 400 A: 30 s, 1,200 A: 1 s
Maximum
allowable input Gate signal: 4 to 20 mA 40 mA DC continuous
Voltage pulse gate in- 30 VDC continuous
put
Input imped- Gate signal: 4 to 20 m 50 Ω max.
ance Voltage pulse gate in- 4 kΩ min.
put
Weight Approx. 200 g
Memory protection Non-volatile memory (number of writes: 100,000 operations)
Installation environment Installation Category 2, Pollution Class 2
Approved standards UL61010-1 and CAN/CSA C22.2 No.61010-1
EN 61010-1 (IEC 61010-1)
EMI: EN61326-1 Industrial electromagnetic environment
Radiated Interference Electromagnetic Field Strength: EN55011 Group 1, class A
Noise Terminal Voltage: EN55011 Group 1, class A
EMS: EN61326-1 Industrial electromagnetic environment
ESD Immunity: EN61000-4-2: 4 kV (contact discharge)
8 kV (air discharge)
EMC Electromagnetic Immunity: EN61000-4-3: 10 V/m 1 kHz sine wave amplitude modulation
(80 MHz to 1 GHz)
Fast Transient Burst Immunity: EN61000-4-4: 2 kV (power line)
1 kV (I/O signal line)
Surge immunity: EN61000-4-5: 1 kV (line to line, power line)
2 kV (line to ground, power line)
Conducted Noise Immunity EN61000-4-6: 3 V (0.15 to 80 MHz)
Voltage Dip/Interrupting Immunity EN61000-4-11: 0.5 cycle, 0.180°,100% (rated voltage)
Note: For phase control, the accuracy is the value when the control value of the power regulator is 100% (when the waveform of the heater current
is a sine wave). “rdg” is the error in the reading of the input current.
*1. The Current Transformers are sold separately.
*2. The values for measurement current apply when the K8AC-H is used in combination with a Current Transformer.
5
K8AC-H
Current Measurement Ranges by Model I/O Ratings
Relay Contact Output
Item Model K8AC-H@1@@-FLK K8AC-H@2@@-FLK K8AC-H@3@@-FLK Item Load Resistive load (cosφ = 1)
Current
measure- 0.200 to 2.200 A AC 2.00 to 22.00 A AC 20.0 to 200.0 A AC Rated load 125 VAC, 0.3 A, 30 VDC, 1 A
ment Maximum contact voltage 125 VAC, 60 VDC
range
200 A 200.0 A Maximum contact current 1A
Maximum switching capaci- 37.5 VA, 30 W
ty
Minimum applicable load
100 A (failure rate P value, refer- 5 VDC, 10 mA
ence value)
20 A 22.00 A Mechanical life expectancy 50,000,000 operations min. (at a switching
2.200 A 20.0 A frequency of 18,000 times/h)
2A Electrical life expectancy
0.200 A 2.00 A (Ambient temperature con- 100,000 operations min. (at rated load and
K8AC-CT200: dition: 20°C) switching frequency of 1,800 times/h)
Current K8AC-CT20S: 5.8-mm through-hole diameter 12-mm through-hole
Trans- or diameter Transistor Output
or
former K8AC-CT20L: 12-mm through-hole diameter K8AC-CT200L:
30-mm through-hole Maximum load voltage 12 to 24 VDC (+10%, −15%)
diameter
Maximum load current 50 mA
OFF leakage current 100 μA max.
ON residual voltage 1.5 V max.
Communications Specifications
Item Communications RS-485
Transmission method Two-wire, half-duplex
Synchronization method Start-stop synchronization
Baud rate 1,200, 2,400, 4,800, 9,600, or 19,200 bps
Transmission code ASCII
6
K8AC-H
Connections
Terminal Arrangement
K8AC-H2@@@-FLK K8AC-H1@@@-FLK
Current inputs Gate input Communications Current inputs Gate input Communications
K8AC-H2@C@ K8AC-H2@P@ K8AC-H1@C@ K8AC-H1@P@
CT1 CT2 Voltage pulse Linear current CT1 CT2 Voltage pulse Linear current
12 VDC or 4 to 20 mA DC RS-485 12 VDC or 4 to 20 mA DC RS-485
24 VDC 24 VDC
A(−) B(+) A(−) B(+)
7 8 9 10 11 12 11 12 13 14 7 8 9 10 11 12 11 12 13 14
7 8 9 10 11 12 13 14 7 8 9 10 11 12 13 14
1 2 3 4 5 6 1 2 3 4 5 6
Power supply voltage Outputs Power supply voltage Outputs
K8AC-H2@@N K8AC-H2@@C K8AC-H1@@T K8AC-H1@@C
COM COM COM
1 2 4 5 6 1 2 4 5 6 4 5 6
3 4 5 6 125 VAC, 12 to 24 VDC, 125 VAC,
100 to 240 VAC 12 to 24 VDC, 12 to 24 VDC, 0.3 A AC 100 to 240 VAC 50 mA DC 0.3 A AC
50 mA DC 50 mA DC 30 VDC, 30 VDC,
1 A DC 1 A DC
Terminals Name Description Applicable models
1 to 2 Power supply voltage Connect to the operating power supply. All models Note: 1. Terminals 4 to 6:
3 to 4, K8AC-H2@@N Alarm output
terminals. Depend
5 to 6 Outputs SSR open or short circuit detection results. (transistor output) on the output type
5 to 4, Outputs Outputs heater burnout or layer short circuit detection results. K8AC-H1@@T (relay contact
6 to 4 (NPN open-collector output) output or transistor
output).
5, 6 to 4 Outputs an OR of the status of all alarms. K8AC-H@@@C (relay output) 2. Terminals 11 and
7 to 8 Connect to CT1. Current input from CT1 secondary-side output. 12: Gate input
Current inputs All models terminals. Depend
9 to 10 Connect to CT2. Current input from CT2 secondary-side output. on the heater
Connect to gate signal (voltage pulse). K8AC-H@@C@ control type (ON-
11 to 12 Gate input OFF/SSR control
Connect to a 4 to 20-mA gate signal. K8AC-H@@P@ or cyclic/phase
13 to 14 Communications Connect to host device for RS-485 communications. All models control).
Current Input Circuits Output Circuits
CT Inputs (Heater Current) Contact Outputs
+12 V COM
7 − A/D 4
+ conversion
CT1 Relay
8 drive 5 N.C. contact
circuit
9 − A/D 6 N.O. contact
+ conversion
CT2 Note: For contact outputs, the same outputs are used for SSR error
10 and for heater burnouts and heater layer short circuit alarm
outputs.
Transistor Output
K8AC-H2@@N-FLK K8AC-H1@@T-FLK
Transistor 4
drive SSR alarm output 4 COM
circuit 3
Transistor 6 Heater burnout,
drive heater layer short circuit, 5 SSR alarm output
circuit 5 overcurrent alarm output Transistor
drive circuit
The transistor output of the K8AC-H2@@N uses a photocoupler for
isolation with the internal circuits, and so either an NPN open- Transistor 6 Heater burnout, heater layer short
collector output or a PNP equivalent output can be used. drive circuit circuit, overcurrent alarm output
NPN Output PNP Equivalent Output
Load Load
Load power supply Load power supply
7
K8AC-H
External Connection Example
Wiring Method When Using the K8AC-H with SSR Control Heaters
Power supply Operation Description
• If the heater current detected at either CT1 or CT2 falls below the
RS-485 burnout alarm set value, an alarm is output. The burnout alarm set
value can be set separately for CT1 and CT2.
Transistor Output No burnout alarm is output, however, when the temperature con-
1 2 13 14 K8AC-H2@@N-FLK troller control output is OFF.
3 Burnouts are detected only while the temperature controller control
3 output is being input to the gate input terminals (11 and 12).
4 Faulty outputs do not occur because heater burnout detection is
4 linked with the temperature controller.
5 • The minimum burnout detection time is 200 ms. Shorter burnouts
are not detected.
6 5 • Turn ON the voltage fluctuation compensation function (default: OFF)
6 to detect power supply voltage fluctuations and automatically compen-
sate the burnout alarm value. Also, turn ON the voltage fluctuation
7 8 9 10 11 12 compensation function to detect minor current fluctuations.
Correct Usage
Temperature • Always take the power supply voltage from the primary side of the SSR.
SSR Controller
(DC voltage output) • Use temperature controllers with a 12 or 24-VDC voltage output
(30 VDC max.).
• CT1 and CT2 are special products. Use the K8AC-CT@@.
CT1 • The CTs do not have polarity.
CT2 • Connect only one CT for single-phase heaters.
• Connect two CTs for three-phase heaters.
• For three-phase heaters, always set the burnout alarm set values
for both CT1 and CT2.
Heater
Wiring Method When Using the K8AC-H with ON/OFF Control Heaters
Power supply Operation Description
RS-485 • If the heater current detected at either CT1 or CT2 falls below the
burnout alarm set value, an alarm is output. The burnout alarm set
Transistor Output value can be set separately for CT1 and CT2.
1 2 13 14 K8AC-H2@@N-FLK No burnout alarm is output, however, when the temperature con-
troller control output is OFF.
3 3 Burnouts are detected only while the temperature controller control
output is being input to the gate input terminals (11 and 12).
4 4 Faulty outputs do not occur because heater burnout detection is
linked with the temperature controller.
5 • The minimum burnout detection time is 200 ms. Shorter burnouts
5 are not detected.
6 6 • Turn ON the voltage fluctuation compensation function (default: OFF)
to detect power supply voltage fluctuations and automatically compen-
7 8 9 10 11 12 sate the burnout alarm value. Also, turn ON the voltage fluctuation
compensation function to detect minor current fluctuations.
24-VDC Correct Usage
power supply Temperature
Contactor X Controller • Always take the power supply voltage from the primary side of the SSR.
(relay output) • Use a temperature controller with relay output.
• The input to the gate input terminals (11 and 12) must be a DC volt-
CT1 age input, so wire the 24-VDC power supply as shown in the dia-
gram to the left.
CT2 • CT1 and CT2 are special products. Use K8AC-CT@@.
• The CTs do not have polarity.
• Connect only one CT for single-phase heaters.
• Connect two CTs for three-phase heaters.
Heater • For three-phase heaters, always set the burnout alarm set values
for both CT1 and CT2.
8
K8AC-H
Wiring Method When Using the K8AC-H with Cyclic Control Heaters
Power supply Operation Description
RS-485 • If the heater current detected at either CT1 or CT2 falls below the
burnout alarm set value, an alarm is output. The burnout alarm set
Transistor Output value can be set separately for CT1 and CT2.
1 2 13 14 K8AC-H2@@N-FLK No burnout alarm is output, however, when the temperature con-
troller control output is OFF.
3 3 Burnouts are detected only while the temperature controller control output
4 is being input to the gate input terminals (11 and 12). Burnout is detected
4 with no errors because the automatic adjustment of burnout alarm level is
linked to the temperature controller control output (4 to 20 mA).
5 • Burnout is detected when control outputs from the temperature con-
5 troller are 7 mA min.
6 6 Correct Usage
7 8 9 10 12 11 • Always take the power supply voltage from the primary side of the SSR.
• Use a temperature controller with a 4 to 20-mA current output.
• When you adjust the set value for the burnout alarm, make sure
SSR SSR G32A-EA Temperature that you make the setting with the temperature controller's control
Cyclic
Control Unit 4 to 20 mA current output Controller output at a 100% output.
The burnout detection value is the detection value at 100% output.
Therefore, correct operation will not be possible if the setting is
CT1 made based on a measurement value when the output is not 100%.
• CT1 and CT2 are special products. Use K8AC-CT@@.
CT2 • The CTs do not have polarity.
• Connect only one CT for single-phase heaters.
• Connect two CTs for three-phase heaters.
* Consult with your OMRON representative if multiple heaters are connected • For three-phase heaters, always set the burnout alarm set values
Heater * in parallel different heater capacities, or if a heater with varying heater for both CT1 and CT2.
resistance is used.
Wiring Method When Using the K8AC-H with Phase Control Heaters
Power supply Operation Description
RS-485 • If the heater current detected at either CT1 or CT2 falls below the
burnout alarm set value, an alarm is output. The burnout alarm set
Transistor Output value can be set separately for CT1 and CT2.
1 2 13 14 K8AC-H2@@N-FLK No burnout alarm is output, however, when the temperature con-
troller control output is OFF.
3 3 Burnouts are detected only while the temperature controller control
4 output is being input to the gate input terminals (11 and 12).
4 Burnout is detected with no errors because the automatic adjust-
ment of burnout alarm level is linked to the temperature controller
5 control output (4 to 20 mA).
5 • Burnout is detected when control outputs from the temperature con-
6 6 troller are 7 mA min.
7 8 9 10 12 11 Correct Usage
• Always take the power supply voltage from the primary side of the
contactor.
Power Temperature • Use a temperature controller with a 4 to 20-mA current output.
Regulator 4 to 20 mA current output Controller • When you adjust the set value for the burnout alarm, make sure
that you make the setting with the temperature controller's control
output at a 100% output (20 mA).
CT1 The burnout detection value is the detection value at a 100% out-
put. Therefore, correct operation will not be possible if the setting is
made based on a measurement value when the output is not 100%.
CT2 • Adjust the burnout alarm set value at a 100% output for gradient
settings as well.
• If using the soft startup function with a power regulator, set the soft
* Consult with your OMRON representative if multiple heaters are connected startup function on the K8AC-H as well, to prevent malfunctions.
Heater * in parallel different heater capacities, or if a heater with varying heater • CT1 and CT2 are special products. Use K8AC-CT@@.
resistance is used. • The CTs do not have polarity.
• Connect only one CT for single-phase heaters.
• Connect two CTs for three-phase heaters.
• For three-phase heaters, always set the burnout alarm set values
for both CT1 and CT2.
• When using the power regulator's gradient settings, change the
operation gate current level so that the heater current value is
within the measurement range. (The initial value is 7 mA.)
For details on operating methods, refer to pages 16 to 18.
9
K8AC-H
Heater Connection Methods and Current
Depending on the heater connection method, the current when an error occurs will be as shown in the following table. Refer to this table when
determining burnout alarm set values.
Normal condition Abnormal condition
5A 0A
Single-phase 200 V 1 kW 200 V
5A 0A
8.7 A 7.5 A 5A
200 V 8.7 A 1 kW 7.5 A 8.7 A
Delta 200 V 1 kW
connection 200 V
8.7 A 1 kW 5A
(5 A × 3 ) (5 A × 3× 3 ) (5 A × 3× 1)
2 3
2.9 A 2.5 A 2.5 A
200 V 2.9 A 1kW 2.5 A 2.5 A
Three- Star 200 V 1 kW
phase connection 200 V
2.9 A 1 kW
(5 A × 1 ) (5 A× 1 × 3 ) (5 A× 1 × 3 )
3 3 2 3 2
5A 2.5 A 5A
200 V 8.7 A 1 kW 5A
V 200 V
connection 200 V
5A 1 kW 2.5 A
(5 A × 3 = 8.7 A) (5 A × 1 ) (5 A × 1)
2
Note: This is the current for when a 200-V, 1-kW heater is used for single-phase or three-phase operation.
Rate of Change for Currents with Parallel Heaters
The following table shows the current change ratios when multiple heaters of the same capacity are connected in parallel and one of the heater
elements burns out. Use this table for reference when making corrections.
If five single-phase heaters are connected in parallel, the current change when burnout occurs is 20% per heater.
For example, if the current for a single heater is low and the change ratio is very slight, it may not be detected. Therefore take into account the
detection accuracy for the total current when selecting the number of heaters to be connected in parallel.
Connection n=1 n=2 n=3 n=4 n=5
Single- I With one heater
phase n heaters burned out, 0.5 0.67 0.75 0.8
I is 0.
I Number of Current in burned- With one heater
heaters per out phase burned out, 0.6 0.75 0.82 0.86
Star phase = n I is 0.
connection
Current in other 0.87 0.92 0.95 0.96 0.97
phases
I Current in lines
near burned-out 0.58 0.77 0.84 0.88 0.91
phase (Same as 2-
Delta phase.)
connection
Current in other 1 1 1 1 1
Number of heaters phases
per phase = n
Note: 1. The figures in the above table show the current change ratios when burnout occurs for one heater connected in parallel.
2. The numbers represent the current ratio after one heater burns out, with the current prior to the burnout (i.e., the normal current) taken
as 1.
3. In actual operation there may be effects from factors such as load (heater) imbalances, so conduct an actual test for confirmation before
making adjustments if the current change ratio between normal and abnormal operation is slight.
4. Consult with your OMRON representative if multiple heaters are used with different heater capacities.
10
K8AC-H
Operation
Main K8AC-H Functions
The K8AC-H is a digital heater burnout detector that detects heater burnout by measuring the heater current from various power supply systems.
The K8AC-H provides the following functions.
Applicable Heater Control Methods Error Detection
The following heater control methods can be used. The following errors are detected according to status.
ON/OFF Control (Contactor/SSR) Heater Layer Short Circuit Detection (overcurrent
detection).
Layer short circuits can be detected in the heater.
The preset overcurrent detection set value is compared with the
ON heater current and an alarm is output accordingly.
OFF
1 to 99 s
Cyclic Control Set value
Current
ON OFF
0.2 to 3.0 s
Phase Control (Applicable to 4 to 20 mA Current-output Alarm
Temperature Controllers) Transistor output models: ALM indicator lit, ALM transistor output
Relay output models: ALM indicator lit, OR of all detection status output
SSR Short Circuit Detection
If current is measured when there is no gate input, an SSR short
ON circuit error is detected and an alarm is output.
OFF
Half cycle Gate input
Heater Burnout Alarm
The preset burnout detection value is compared with the heater
current and an alarm is output accordingly.
Current
Current measurement
Set value
500 ms 100 ms Alarm
Transistor output models: SSR indicator lit, SSR transistor output
Relay output models: SSR indicator lit, OR of all detection status output
SSR Open Circuit Detection
Alarm If current is not measured during gate input, an SSR open circuit error
is detected and an alarm is output.
Transistor output models: ALM indicator lit, ALM transistor output
Relay output models: ALM indicator lit, OR of all detection status output
Gate input
Current
measurement
Alarm
Transistor output models: SSR indicator lit, SSR transistor output
Relay output models: SSR indicator lit, OR of all detection status output
11
K8AC-H
Voltage Fluctuation Compensation Using the Power Regulator's Gradient Settings
The voltage fluctuation compensation function automatically adjusts The power regulator's gradient settings can be used to prevent
the burnout alarm value of the K8AC-H according to voltage malfunction by setting the operation gate current level. The
fluctuations in the heater circuit. relationship between the gradient settings and output current
The operating value for burnout detection when multiple heaters are depends on the power regulator manufacturer and model, so be sure
connected is set very close to the normal value. Thus, a false burnout to check the characteristics of the power regulator being used before
alarm output will occur if there is a voltage drop in the heater circuit. setting.
The voltage fluctuation compensation function prevents this type of Setting Example
false output. Initial setting: 7 mA
Example: Voltage Drop from 100 V to 95 V in the Heater Circuit
Conditions: Output current Gradient
Voltage fluctuation compensation standard value = 100 V 100% setting 100%
Burnout alarm set value = 10.0 A Measurement range
If the power supply voltage drops from 100% to 95%, the
operating value will also reduced from 100% to 95%.
Burnout alarm operating value = 10.0 A × 95% = 9.5 A
Gate Input 0% Control signal
The gate input provides a sync signal used to link burnout detection
to the control output of the temperature controller. 4 mA 7 mA 20 mA
For SSR control, the voltage output pulse from the temperature Not detected Detected
controller is input. When the power regulator's gradient settings are changed, the
For ON/OFF control, 24 VDC linked to a relay contact of the operation gate current level is set so that the output current is within
temperature controller is input. the measurement range. (In the following diagram, 14 mA is set.)
For cyclic or phase control, a 4 to 20-mA control signal is input. Output current Gradient
If there is no gate input for a Heater Element Burnout Detector, a 100% Measurement range setting 100%
heater burnout alarm would be falsely output when the voltage output
pulse from the temperature controller turns OFF, and there would be Gradient
no way to tell whether it was a false output. setting 50%
Note: The gate input function can be disabled. If it is disabled, Heater
Element Burnout Detector operation will not be linked to the 0% Control signal
temperature controller control signal. (The gate input can be
used as a simple undercurrent relay.) 4 mA 14 mA 20 mA
Power-saving Operation Not detected Detected
If there are no key operations performed within a preset time period, Using Halogen or Other Heaters with Varying
the display automatically turns OFF. Resistance during Phase and Cyclic Control
Power Save Mode When phase control is used with halogen heaters or other pure metal
Standby Time heaters, the heater resistance fluctuates according to the control
level. As a result, high-precision detection of heater burnout is not
possible. The effect on the heater and setting methods depends on
Output Operation Time Charts the heater being used. Therefore, consult with your OMRON
Heater Burnout and Heater Layer Short Circuit representative before using a heater with varying resistance values.
(Overcurrent) Alarms Halogen Heater Resistance Fluctuation Example
Alarm hysteresis In the following example, burnout of one element in a six-element
Heater layer short circuits heater can be detected at a control level of 20 mA, but detection is not
Overcurrent set value possible due to the effect of fluctuating resistance if the control level
Heater current is any lower.
Heater burnout set value Heater resistance
8Ω Three elements
Detectable range burned out
Alarm output 6Ω
ALM indicator lights. ALM indicator lights. One element
SSR Short/Open Circuit Alarm burned out
4Ω Threshold
SSR short-circuit
SSR open-circuit 2Ω Normal
(six elements in parallel)
Alarm output
SSR indicator lights. SSR indicator lights. 0Ω Control signal
4 mA 7 mA 20 mA
12
K8AC-H
Nomenclature
Nomenclature and Operations
K8AC-H2@@@-FLK K8AC-H1@@@-FLK Name Operation
Main display Displays processing values, parameter characters,
and set values.
RUN (Mea- Lights when the power is turned ON and the
surement measurement operation is in progress.
Operation operation) OFF at all other times.
indicators ADJ Lights while in Adjust Mode.
Main display (Adjust) Flashes while in Test Mode.
area OFF at all other times.
SET (Set) Lights while in Set Mode.
Shift key Oper- OFF at all other times.
ation Lights or turns OFF according to gate input status.
Up key indi- Gate pulse:
cators GATE Lights for high voltage pulse; OFF for low
Mode key (Gate) voltage pulse.
Down key Gate signal (4 to 20 mA):
Lights for 4 mA or over; OFF for less than 4 mA.
Level key SSR Lights when an SSR error occurs (open or short
(SSR error) circuit).
* OFF when SSR is normal.
ALM Lights for heater burnout or overcurrent.
(Alarm) * OFF at all other times.
Up key Increments a set value when the set value is in
change status.
Down key Decrements a set value when the set value is in
change status.
Used to check set values while parameters are
Shift key displayed, and to put set values in change status.
Used to shift the set value digit when the set value is
in change status.
Mode key Used to switch the displayed parameter.
Level key Used to change the level.
* Check the specific status using the alarm display parameters on the
main display.
Alarm Indicator Processing Value Display Ranges and Functions
s
Order 7-segment LED Processing Display Display Unit Function
of Alarm display indicator Alarm contents value name characters range
priority characters This is the CT1 heater
1 Heater burnout 1 hbt1 ALM CT1 heater 0100 to current processing value.
indicator lit burnout detected. Heater 1 ct 1 2300 A Alarm operations such as
2 Heater burnout 2 ALM CT2 heater current *1 the heater burnout alarm
hbt2 indicator lit burnout detected. *2 are determined based on
SSR open circuit this processing value.
detected (when This is the CT2 heater
heater current 0100 to current processing value.
3 SSR open circuit SSR cannot be Heater 2 ct 2 2300 A Alarm operations such as
ssro indicator lit detected with current *1 the heater burnout alarm
temperature *2 are determined based on
control gate this processing value.
output ON). *1. The decimal point position depends on the input type.
SSR short circuit K8AC-H@1@@: 0.100 to 2.300
K8AC-H@2@@: 1.00 to 23.00
detected (when K8AC-H@3@@: 10.0 to 210.0
SSR heater current is *2. If the display is below 0100, the bar display “----” will be shown.
4 SSR short circuit ssrs indicator lit detected with
temperature
control gate
output OFF).
5 Heater layer hrs1 ALM CT1 overcurrent
short circuit 1 indicator lit detected.
6 Heater layer hrs2 ALM CT2 overcurrent
short circuit 2 indicator lit detected.
Note: 1. As soon as the cause of an alarm is removed, the alarm is
reset automatically.
2. If multiple alarms occur simultaneously, the one with the
highest priority is displayed.
3. If the mode is changed to Adjust or Set Mode while an alarm
is in effect, the alarm output is reset and the ALM and SSR
indicators turn OFF.
4. If an SSR operation gate current level is set for a model with
phase control or cycle control, alarms will not be output for
SSR short circuits.
13
K8AC-H
Settings Method
Settings Methods for SSR and ON/OFF Control Heaters
Settings Conditions K8AC-H Parameter Setting Procedure
Detecting burnouts in just one heater when ten 300-W rated heaters (Only the minimum settings are shown here. Refer to pages 16 to
are connected in parallel to a single-phase 200-V power supply. 18 for information on how to set parameters.)
The heater is SSR controlled. 1. Turn ON the power to the K8AC-H. The initial status when power
Normal Heater Current and Heater Current with One is turned ON is called Run Mode.
Heater Element Burnout 2. Press the L Key for at least 3 s to change from Run Mode to
Normal current = (300 W × 10 (heaters))/200 V = 15.0 A Adjust Mode (the mode for adjusting burnout alarm set values.)
Current with one burnout = (300 W × 9)/200 V = 13.5 A 3. Set the burnout alarm set values. (AL-1 = CT1 burnout alarm set
Heater burnout alarm set value = value and AL-2 = CT2 burnout alarm set value.)
Set “14.3” to AL-1.
(Normal current + current at malfunction) 15.0 + 13.5 Set the AL-2 burnout alarm set value to “----” so that it will not
2 = 2 = 14.3 A detect heater burnout, because this is a single-phase heater.
4. Change to Run Mode.
Selecting Heater Element Burnout Detector Models Press the L Key while in Adjust Mode for at least 1 s to change
For the above example, K8AC-H12C@-FLK would be selected. to Run Mode.
5. Check operation.
The burnout alarm set value is 14.3 A, so the current input range 2.00 Test heater burnout detection by burning out one heater.
to 22.00 A should be selected. Also check that there are no malfunctions during temperature
SSR control is used, so type C should be selected. (Type C is also control.
selected for ON/OFF control.) Note: The default setting for functions including the voltage
Select the appropriate relay or transistor output specifications, fluctuation compensation function, alarm hysteresis, output
depending on the application. ON-delay time, and SSR error detection function is OFF. Turn
ON any of these functions as required.
Settings Method for Cyclic and Phase Control Heaters
Settings Conditions ON-delay time, and SSR error detection function is OFF. Turn
Detecting burnouts in one heater when five 1,000 W-rated heaters are ON any of these functions as required.
connected to each phase of a three-phase delta-connected 200-V Burnout Alarm Set Value Setting Method
power supply. Setting Method
A power regulator (phase control) performs heater control. • Wire the K8AC-H, temperature controller (4 to 20 mA current
Normal Heater Current and Heater Current With One output type), and power regulator (phase control).
Heater Element Burnout • Press the L Key on the K8AC-H for at least 3 s to change from
Example: When One of Five Single-phase Heaters (R-S) Burns Run Mode to Adjust Mode.
Out • AL-1 (CT1 burnout alarm set value) will be displayed when the
Normal current = 3 (1,000 W × 5 (heaters))/200 V = 43.3 A mode is changed to Adjust Mode. Press the S key once when AL-
Current with one burnout = 43.3 A × 0.91 = 39.4 A 1 is displayed. Next, press the U Key once. The present heater
(Refer to Rate of Change for Currents with Parallel Heaters on current value will be displayed on the main display, so note this as
page 10.) the normal current value. Always have the temperature controller
Heater burnout alarm set value = output at 20.0 mA at this time (See note 1.)
Normal current + current at malfunction = 43.3 + 39.4 = 41.4 A • Next, disconnect one heater and note the heater current in this
2 2 burnout state. Alternatively, use the current when one heater is
burned out (calculated earlier) as the current during malfunction. It
Selecting Heater Element Burnout Detector Models is recommended that the current at an actual burnout is confirmed.
For the above example, K8AC-H13P@-FLK would be selected. • Set the K8AC-H burnout alarm set value based on the results. The
The burnout alarm set value is 41.4 A, so the current input range 20.0 burnout alarm set value is set at the mid-point between the normal
to 200.0 A should be selected. current and the current at malfunction, taking errors and variations
Phase control is used, so type P should be selected. (Type P is also in heater capacity into consideration.
selected for cyclic control.) • In this setting example, the set value for AL-2 (CT2 burnout alarm
Select the appropriate relay or transistor output specifications, setting) is the same as the set value for AL-1. (See note 2.)
depending on the application. Note: 1. The K8AC-H automatically adjusts burnout alarm levels to
compensate based on the temperature controller current
K8AC-H Parameter Settings Procedure output. The burnout alarm value must be set when the
(Only the minimum settings are shown here. Refer to pages 16 to temperature controller output is at 100% (20 mA), so be
18 for information on how to set parameters.) sure to have the temperature controller at 20 mA output.
1. 2. If the heater capacity is unbalanced, the burnout alarm
Turn ON the power to the K8AC-H. The initial status when power values for CT1 and CT2 may not be the same.
is turned ON is called Run Mode.
2. Press the L Key for at least 3 s to change from Run Mode to
Adjust Mode (the mode for adjusting burnout alarm set values.)
3. Change from Adjust Mode to Set Mode (the default settings mode
for all functions). The password “0169” is required to move to Set
Mode.
4. Set the heater control method parameter to PH-3 (three-phase
control).
The default setting is PH-1 (single-phase control).
Note: Set the parameter to CYCL (cyclic control) when using
cyclic control.
5. Press the L Key for at least 1 s to change from Set Mode to Adjust
Mode. Press the L Key again for at least 1 s to change from
Adjust Mode to Run Mode.
Note: The default setting for functions including the voltage
fluctuation compensation function, alarm hysteresis, output
14
K8AC-H
Measurement Monitor Value Display Ranges and Functions
Other than measuring the heater current, the K8AC-H can measure the power supply voltage, maximum/minimum current, maximum/minimum
voltage, and other values. The measurement data can be monitored from a host using RS-485 communications. The measurement monitor value
names, display ranges, and functions are given in the following table.
Measurement monitor Display char- Display range Unit Function
value name acters
This is the measurement value of the K8AC-H power supply voltage. When the voltage
Power supply voltage sce 0085 to 0264 V fluctuation compensation function is enabled, the heater burnout determination based on
this voltage is automatically compensated.
Heater 1 maximum current max1 0100 to 2300 A
*
Heater 1 minimum current min1 0100 to 2300 A
* These hold the maximum and minimum values for each processing value.
Heater 2 maximum current max2 0100 to 2300 A • The maximum and minimum heater currents after the power is turned ON or after a
* maximum or minimum reset are displayed.
Heater 2 minimum current • The values are not saved when power is interrupted.
* min2 0100 to 2300 A • The current values are not refreshed when startup lock is in effect and when the gate
input is enabled but the gate input is OFF.
Maximum power supply maxs 0085 to 0264 V • Measurement values for power supply voltages are always refreshed.
voltage *
Minimum power supply mins 0085 to 0264 V
voltage *
This value counts the total number of alarms output for heater burnout, SSR open and
short circuits, and heater layer shorts.
• The count is refreshed each time an alarm is output, and it is saved in non-volatile
Number of alarm outputs acnt 0000 to 9999 Outputs memory.
• The value is saved when power is interrupted.
• The number of outputs is not counted for the test function.
• After counting to 9999, the value is held at 9999 and any further alarms are not
counted. To return the count to 0, perform a reset.
This holds the CT1 or CT2 processing value when a heater burnout alarm is output.
Processing value for alarm memo 0100 to 2300 A • This is the most recent processing value, and it is refreshed each time a heater
output burnout alarm occurs.
• The value is not saved when power is interrupted.
This is the total run time value from when power is turned ON or the processing value is
reset until an alarm occurs.
• The total time is recorded in non-volatile memory approximately once per hour. If
Run time otim 0000 to 9999 × 10h power is interrupted within the hour, however, the data since the beginning of the hour
is lost and the total starts over from when the time was last saved.
• The total is stopped during heater burnout alarm output. When the alarm is cleared,
the total resumes from the time just before the alarm occurred.
Heater 1 input shift display This is the shift value for displaying the CT1 heater current measurement set in
current isc1 −999 to 999 digit measurement parameter CT1.
• The value is saved when power is interrupted.
Heater 2 input shift display This is the shift value for displaying the CT2 heater current measurement set in
current isc2 −999 to 999 digit measurement parameter CT2.
• The value is saved when power is interrupted.
* Each measurement value can be individually reset. Refer to the K8AC-H Digital Heater Element Burnout Detector User’s Manual (Cat. No. N132)
for operating procedures.
Modes
Groups of setting items are called “modes.” The K8AC-H has five modes.
Mode Function Alarm operation
Run Mode This is the normal operating mode, used for receiving inputs, executing heater burnout outputs, etc. Executed
Operation goes into Run Mode immediately after power is turned ON.
Adjust Mode This mode is used to change comparatively frequently set parameters, such as alarm value settings. Stopped
This also the mode for entering the password to move to the Set Mode.
Set Mode This mode is used to make the initial settings for the various functions. Stopped
Protection Settings This mode is used to make settings to prevent unintended key operations. The protected modes are not displayed, Stopped
Mode preventing changes to set values.
Test Mode This mode is used to simulate inputs with key operations to test alarm outputs. Executed
Gate Mode This mode sets the gate current value that stops an alarm or detection. Executed
Note: If more than five minutes elapses with no operations performed in the Protection Settings Mode, Adjust Mode, or Set Mode, the status will
return automatically to the processing value display. If this occurs while settings are in progress, it may cause unintended operations in the
processing value display. Be careful not to allow this to happen.
Settings Data Notation
The letters of the alphabet in settings data are displayed as shown below.
a b c d e f g h i j k l m n o p q r s t u V w x y z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
15
K8AC-H
Operating Procedures
Moving between Modes
Press the D To Gate Mode
key for at least 1 s. Gate Mode When the D key is pressed for at least one second in Run Mode, the
Power ON Press the D mode will be switched to Gate Mode. To return to Run Mode from
Press the key for at least 1 s. Gate Mode, press the D key for at least one second.
L and M Press the S
key for at least 1 s.
keys. To Test Mode
1234 Run Mode Test Mode When the S key is pressed for at least one second in Run Mode, the
When the Press the S mode will be switched to Test Mode. To return to Run Mode from Test
key for at least 1 s.
key is Mode, press the S key for at least one second.
Press the L released Press the L key
and M keys for When the key for at least 1 s. To Set Mode (Password Input)
5 s. is released
Protection A special operation is required to move to the Set Mode.
Settings Mode Press the Press the 1234 Use the following procedure.
L and M L key for Procedure
keys for at at least 1s.
least 1 s. Hold down for at
Adjust Mode least another 2 s. amoV A. Move to the Adjust Mode and use the M key to
display the parameter for moving to the Set Mode.
Press the L key Password: 0169 · The parameter characters are "amoV".
for at least 1s.
Set Mode 0 B. Press the S key to display the set value
(password).
To Adjust Mode
When the L key is pressed for one second in Run Mode, the 7- 0000 C. Press the S key again to enable changing
segment display will begin to flash. If the key is held down for another the password.
two seconds, the mode will be switched to Adjust Mode.
To return to Run Mode from Adjust Mode, press the L key for at least 0169 D. Use U, D, and S keys to set the password.
one second. The password is 0169.
To Protection Settings Mode · Press the M key.
When the L and M keys are pressed for one second in Run Mode, · If the password is correct, the mode will change to
the 7-segment display will begin to flash. If the keys are held down for the Set Mode.
· If the password is incorrect, the next parameter will
another five seconds, the mode will be switched to Protection Settings be displayed while still in Adjust Mode.
Mode. To return to Run Mode from Protection Settings Mode, press amoV S 0 S 0000 S 0169
L and M keys for at least one second. M M M
M
When password When password
Next parameter is incorrect is correct
in Adjust Mode Set Mode init
Setting the Parameter
The value set for each parameter is called the “set value.” Set values Procedure
include both numbers and characters. A. Press the S key while a parameter is displayed to
The status when a set value is displayed is called “monitor status,” go into monitor status. The set value for that
and when it can be changed it is called “change status.” parameter will be displayed.
Use the following procedure to display and change set values. B. If the set value is not to be changed, press the M
Note: key while in monitor status to switch to the next
If a set value is out of parameter.
range, either too high or too C. Press the S key again while in monitor status to
low, the maximum or enable the changing set value.
minimum value will · The place where the set value can be changed will
automatically be set. For begin to flash.
models with a current input
of 0.200 to 2.200 A, for D. Use the S, U, and D keys to change the set
example, the maximum value.
value is 2.200 and the E. Press the M key to save the changed set value in
minimum value is 0.200. internal memory and switch to the next parameter.
· Changed set values will not be saved in memory if
the mode is changed by another key operation
without first pressing the M key.
M Monitor status Change status
al-1 S 2000 S 2000
M M M Use the S, U, and
D keys to change
the set value.
To next parameter
16
K8AC-H
Parameter List
The setting items in each mode are called “parameters.”
Parameters can be switched by using the M key.
Protection Mode *3 Adjust Mode *3 Set Mode *3
aspt al-1 init
Setting change protection Burnout alarm All initialization
setting value 1 dsmd
wtpt al-2 sini Display mode
Setting change protection Burnout alarm Set value initialization
setting value 2 dsrf
ON VfcV 1 s min. pini Display
refresh time
Powe r Voltage fluctuation Processing value
compensation standard value initialization u no
5s min. 1 s min. *1 hys1
amoV Unit number
Run Mode Password for Alarm hysteresis 1 bps
1 s min. moving to Set
1234 Mode: 0169 hys2
Baud rate
(Processing value Alarm hysteresis 2 len
display status) 3 s min.
gate Data length
ct 1 Gate input function sbit
Heater 1 current comp
Stop bits
ct 2 Voltage fluctuation
Test Mode compensation standard value prty
Heater 2 current stim Parity bit
i s c 2 s c e 1 s min. test
Startup lock time goht *4
Heater 2 input shift Power supply voltage An alarm is output if
display current measurement value the test value falls odly Gate OFF
below the burnout output hold time
1 s min. alarm value 1 setting.
i s c 1 m a x 1 Output ON-delay time
Heater 1 input shift Heater 1 nct1
display current maximum current soft Number of
o t i m m i n 1 CT passes 1
Soft startup time
RUN time Heater 1 ctr1
minimum current Gate Mode *2 ssht
CT ratio 1
memo max2 SSR short circuit
detection function ndp1
Processing value Heater 2 1 s min. g-lV
for alarm output maximum current sopn Setting 1 for number of
Alarm or detection is effective digits to be displayed
acnt min2 stopped if the gate SSR open circuit after the decimal point
current value falls detection function
Number of Heater 2 1 s min. below the set value. nct2
alarm outputs minimum current hrst
Number of
min5 maxs Heater layer short circuit CT passes 2
Minimum power Maximum power detection function ctr2
supply voltage supply voltage
hral CT ratio 2
Measurement Heater layer short circuit ndp2
parameters *3 alarm set value
Setting 2 for number of
msmd effective digits to be displayed
*2 after the decimal point
Heater control Note:
method Displayed only for
dsel the K8AC-H2@@@.
Switchable sdly
Parameter Display display
: Displayed for all models and settings. psmd SSR ON delay
: May not be displayed depending on the model or settings. Power save sglV
mode
pstm SSR operation
Power save gate current level
mode standby
time cyct
Cycle time
*1. Displayed when the Selectable Protection Level parameter is set to 0.
*2. Displayed by the K8AC-H@@P@-FLK.
*3. If more than five minutes elapses with no operations performed in Protection Settings Mode, Adjust Mode, Set Mode, or for a measurement
parameter, the status will return automatically to the processing value display.
If this occurs while settings are in progress, it may cause unintended operations to be performed in Run Mode (i.e., with measurement values
displayed). Be careful not to allow this to happen.
*4. Displayed by the K8AC-H@@C@-FLK.
17
K8AC-H
Parameter Defaults and Descriptions Note: Shaded parameters must always be set regardless of the
measurement method.
Item Parameter name Description Param- Setting range Default
Mode eter
Restricts access to Adjust Mode or Set Mode from Run Mode.
Protec- Setting Change Protection 0: Access enabled to both Adjust Mode and Set Mode. aspt 0 to 2 0
tion 1: Access enabled to Adjust Mode and disabled to Set Mode.
Mode 2: Access disabled to both Adjust Mode and Set Mode.
Setting Value Change Prohibits changes to set values. wtpt ON/OFF OFF
Prohibition
Burnout Alarm K8AC-H@1 Sets the output operation value for the burnout alarm. 0.200 to 2.200 A 1.000 A
Value 1 K8AC-H@2 The burnout alarm function can be disabled by setting the set value to al-1 2.00 to 22.00 A 10.00 A
K8AC-H@3 “−”. 20.0 to 200.0 A 100.0 A
Adjust Burnout Alarm K8AC-H@1 Sets the output operation value for the burnout alarm. 0.200 to 2.200 A 1.000 A
Mode Value 2 K8AC-H@2 The burnout alarm function can be disabled by setting the set value to al-2 2.00 to 22.00 A 10.00A
K8AC-H@3 “−”. 20.0 to 200.0 A 100.0 A
Voltage Fluctuation Sets the standard voltage used by the voltage fluctuation
Compensation Standard Value compensation function. The fluctuation compensation function vfcv 100 to 240 VAC 100 V
operates in respect to this set value.
All Initialization Returns all set values and measurement values to their default init ON/OFF OFF
settings.
Set Value Initialization Returns all set values to their default settings. sini ON/OFF OFF
Processing Value Initialization Returns all measurement values to their default settings. pini ON/OFF OFF
Alarm Hysteresis 1 Sets hysteresis for the alarm output value for burnout detection hys1 1 to 999 10
(undercurrent) and heater layer short circuits (overcurrent) for CT1.
Alarm Hysteresis 2 Sets hysteresis for the alarm output value for burnout detection hys2 1 to 999 10
(undercurrent) and heater layer short circuits (overcurrent) for CT2.
Gate Input Function Turns the gate input function ON and OFF. If the gate input is turned gate ON/OFF ON
OFF, application as a simple ammeter is possible.
Voltage Fluctuation Turns the voltage fluctuation compensation function ON and OFF. comp ON/OFF OFF
Compensation Reference Value
Startup Lock Time Sets the lock time for the startup lock. stim 0 (OFF) to 255 s 0 (OFF)
Output ON-Delay Sets the output delay time. Set this parameter to set the operating time. odly 0.0 (OFF) to 99.9 s 0.0 (OFF)
Soft Startup Time Sets the soft startup time. Set this parameter only when using a soft soft 0.0 (OFF) to 99.9 s 0.0 (OFF)
start function with the power regulator.
SSR Short Circuit Detection Turns the SSR short circuit detection function ON and OFF. ssht ON/OFF OFF
SSR Open Circuit Detection Turns the SSR open circuit detection function ON and OFF. sopn ON/OFF OFF
Heater Layer Short Circuit Turns the heater layer short circuit (overcurrent) detection function ON
Detection (Overcurrent and OFF. hrst ON/OFF OFF
Detection)
Heater Layer Short K8AC-H@1 Sets the operating level for heater layer short circuit (overcurrent) 0.200 to 2.200 A 2.000 A
Circuit Alarm Level K8AC-H@2 alarms. hral 2.00 to 22.00 A 20.00 A
(Overcurrent Alarm K8AC-H@3 The heater layer short circuit alarm level is the same for both CT1 and 20.0 to 200.0 A 200.0 A
Set Value) CT2.
Heater Control Method *1 Sets the control method of the cyclic/phase control heater. msmd PH1, PH3, CYCL PH1
Set Mode Switchable Display Sets the CT for which to normally display the current. dsel CT1, CT2 CT1
Power Save Mode Turns entering the power save mode ON and OFF. psmd ON/OFF OFF
Power Save Mode Standby Time Sets the time to enter power save mode. pstm 10 to 300 s 60 s
Display Mode Sets a 7-segment (NORM). full-span comparison (CMP), or bar (BAR) dsmd NORM, CMP, BAR NORM
display.
Display Refresh Time Sets the refresh time for the display. dsrf 0.2 s, 0.5 s, 1.0 s, FAST 0.5 s
Unit Number Sets the unit number for RS-485 communications. u no 0 to 64 0
Baud Rate Sets the baud rate for RS-485 communications. dps 1200, 2400, 4800, 9600, 9600
19200
Data Length Sets the data length for RS-485 communications. len 7, 8 7
Stop Bits Sets the number of stop bits for RS-485 communications. sbit 1, 2 2
Parity Bit Sets the parity for RS-485 communications. prty EVEN, ODD, NONE EVEN
Gate OFF output hold time *2 Sets the time from when the gate signal goes OFF until the burnout goht 0 to 999 s 2s
alarm output turns OFF.
Number of CT passes 1 Sets the number of times the conductor for CT1 is passed through the nct1 1 to 99 times 1 time
current transformer.
CT Ratio 1 Sets the CT ratio for CT1. ctr1 1 to 999 1
Setting 1 for number of effective Sets the number of effective digits to be displayed after the decimal Depends
digits to be displayed after the point for the CT1 current display. ndp1 0 to 3 places on the
decimal point model.
Number of CT passes 2 Sets the number of times the conductor for CT2 is passed through the nct2 1 to 99 times 1 time
current transformer.
CT Ratio 2 Sets the CT ratio for CT2. ctr2 1 to 999 1
Setting 2 for number of effective Sets the number of effective digits to be displayed after the decimal Depends
digits to be displayed after the point for the CT2 current display. ndp2 0 to 3 places on the
decimal point. model.
18
K8AC-H
Item Parameter name Description Param- Setting range Default
Mode eter
SSR ON delay Sets the SSR ON-delay time. sdly 0.0 (OFF) to 99.9 s 0.2 s
Sets the gate current level for SSR operation.
SSR operation gate current level (This setting is valid only when cyclic or phase control is selected as sglv 4.0 to 20 mA 7.0 mA
Set Mode the heater control method.)
Sets the cycle time.
Cycle time *3 (This setting is valid only when cyclic control is selected as the heater cyct 0.2 to 3.0 s 0.2 s
control method.)
Gate Gate Current Level *1 Sets the gate current value that stops an alarm, detection, or output. g-lv 7.0 to 20.0 mA 7.0 mA
Mode
*1. Displayed by the K8AC-H@@P@-FLK.
*2. Displayed by the K8AC-H@@C@-FLK.
*3. You must restart the K8AC after you change the setting of the cycle time.
Dimensions (Unit: mm)
Digital Heater Element Burnout Detectors
K8AC-H2@@@-FLK
35 2.1 100
To remove a wire, insert the recom-
mended flat-blade screwdriver straight
into the hole under the push-in terminal
of the wire to enable easily remove it.
90
1.7 4.5
6
K8AC-H1@@@-FLK
35 100
90
Recommended Tools Recommended Crimp Terminals
Recommended Flat-blade Screwdriver Recom-
Manufacturer: Phoenix Contact Terminals Recommended crimp terminals mended
Model number: SZF0.4 × 2.5 wire gauge
M3 crimp terminals (Width: 5.8 mm max.)
Crimper for Bar Terminals (Crimping Tool) 5.8 mm max. AWG16 to
Manufacturer: Phoenix Contact 1 and 2 AWG18
Model number: CRIMPF0X UD6
Recommended power line diameters: AWG10 to AWG24 5.8 mm max.
M2 bar terminals: Al 0.34-8TQ (Phoenix Contact) AWG22
3 to 14 M2 bar terminals: Al 0.5-8WH (Phoenix Contact) AWG20
M2 bar terminals: Al 0.75-8GY (Phoenix Contact) AWG18
Note: Securely tighten the terminal screws to the following torque:
Power supply terminals: 0.5 N·m
I/O terminals: 0.23 N·m
19
K8AC-H
Optional Parts (Sold Separately)
Current Transformer 15 1.2 dia. 2.8
K8AC-CT20S 0.5
5.5 7
5.8 dia.
25
10.5
21 2.5
Two, 3.5 dia.
10
30
40
Current Transformer Accessories with K8AC-CT20L: Connection Example
K8AC-CT20L 30 2.36 dia. Contact
9 Contact
Plug
Approx. 3 dia. Lead
40
18
12 dia.
40 15 Plug
Two, M3
Depth: 4 max. Approx. 6 dia.
15 (22)
5 30
Current Transformer 30
K8AC-CT200 (Pre-wired Leads) 5
100
40
12 dia.
40 15
Two, M3
Depth: 4 max.
15
5 30
Current Transformer 9.3 9.3
K8AC-CT200L 1.7 1.7
11 4.7
63 20
54 Four, M4 × 6 screws
50 17
8.5 Mounting Hole Dimensions
13.5
Two, M5 screw holes
34.5 or two, 5.5-dia. holes
81.5
33.5 76
6
14.5 57 14.5 30 dia.
86
5.2
10 20
10
1.8 Note: Wire only the K and L terminals to the K8AC-H.
4.1 76 5.9 Leave the Kt and Lt terminals open.
20
K8AC-H
Safety Precautions
Precautions for Safe Use Mounting the K8AC-H
• Pull down the hook on the bottom of the K8AC-H, and then catch
The following precautions are essential to ensure safety. Always heed the hook on the top of the K8AC-H onto the DIN Track and press
these precautions. the K8AC-H onto the DIN Track until it locks into place.
1. Do not use or store the Product in the following locations.
• Outdoors or in locations subject to direct sunlight, wind, or rain
• Locations subject to dust, metal powder, or corrosive gases (in
particular, sulfuric or ammonia gas)
• Locations subject to static electricity or noise
• Locations subject to flooding or exposure to oil
2. Use DIN Track for installation and mount the Product in the correct
direction.
3. Do not touch the terminals when power is being supplied. Electric Removing the K8AC-H
shock may occasionally occur.
4. Be sure you understand the contents of the Instruction Sheet and • Pull down on the hook with a flat-blade screwdriver and lift up on
User’s Manual and handle the Product according to the the K8AC-H.
instructions provided.
5. Check all terminal numbers and polarity when wiring and wire all
connections correctly.
6. Tighten terminal screws to the following torque.
Power supply terminals: 0.5 N·m
7. Use the Product within the specified temperature and humidity
ranges.
8. Do not use the product in locations subject to flammable or
explosive gases. Explosions may occasionally occur if the product
is used in such locations.
9. Do not install the Product in any way that would place a load on it. Noise Countermeasures
10.Use the Current Transformer specified by OMRON. 1. Do not install the product near devices generating strong high
11.Install an external switch or circuit breaker that complies with frequency waves or surges.
applicable IEC60947-1 and IEC60947-3 requirements and label it 2. When using a noise filter, check the voltage and current and install
clearly so that the operator can quickly turn OFF the power. it as close to the product as possible.
12.The product must be handled by personnel who have knowledge 3. In order to prevent inductive noise, wire the lines connected to the
of electrical systems. product separately from power lines carrying high voltages or
Precautions for Correct Use currents. Do not wire in parallel with or on the same cable as power
lines.
The following precautions are essential to ensure correct use. Always Other measures for reducing noise include running lines along
heed these precautions. separate ducts and using shield lines.
1. Do not use the product in the following locations. Wiring
• Places subject to radiant heat from heat generating devices. • Do not touch terminals or perform wiring while power is supplied to
• Places subject to vibrations or physical shocks. the product. Doing so may result in injury or malfunction.
2. Make sure to use setting values appropriate for the controlled • Wire to the correct terminal number. Incorrect wiring may result in
object. Failure to do so can cause unintended operation, and may damage to or burning of components.
result in accident or corruption of the product.
3. Do not use thinner or similar solvent for cleaning. Use commercial Wiring the Push-in Terminals
alcohol. • Directly insert the ferrule in the hole of the terminal to be wired.
4. When discarding, properly dispose of the product as industrial
waste.
5. To measure correct values, perform aging for approximately 15
minutes.
6. Only use this product within a board whose structure allows no 7 8 9 10 11 12 13 14
possibility for fire to escape. RUN ADJ SET GATE SSR ALM
Installation 8. 8. 8. 8.
1. When wiring, use only recommended crimp terminals.
2. Do not block areas around the product for proper dissipation of
heat. (If you do not secure space for heat dissipation, life cycle of
the product will be compromised.) Removing Wires from the Push-in Terminals
• Insert the recommended flat-blade screwdriver straight into the
hole to pull out the wire.
7 8 9 10 11 12 13 14
RUN ADJ SET GATE SSR ALM
8. 8. 8. 8.
U
21
K8AC-H
Q&A
Q Why does the current measured by the K8AC-H decrease
during cyclic or phase control?
To enable measuring the current accurately for the heater
control value, the K8AC-H@@P@-FLK uses the current input
waveform from a gate input and the Current Transformer to
compensate the measured current value and burnout alarm
value. The compensated current value is displayed, so it
appears as if the measured current is lower during cyclic or
phase control, but the K8AC-H@@P@-FLK is operating
correctly.
Q How do I set the burnout detection alarm of the K8AC-
H@@P@-FLK when phase control is used?
Set the burnout alarm value of the K8AC-H@@P@-FLK based
on the current measurement value with the heater output at
100%. (This is because the burnout detection alarm of the
K8AC-H@@P@-FLK depends on the control input.)
When you set the burnout alarm value, make sure that you
make the setting based on the current measurement value
when the control of the power regulator is 100% or the rated
voltage is applied to the heater.
Heater current Heater current
Heater Burnout Alarm Value
The heater burnout alarm value shifts
according to the control input (4 to
Heater burnout 20 mA) from the temperature controller.
alarm value
4 mA 7 mA 20 mA
Control output from temperature controller
22
Warranty and Application Considerations
Warranty and Limitations of Liability
WARRANTY
OMRON's exclusive warranty is that the products are free from defects in materials and workmanship for a period of one year (or
other period if specified) from date of sale by OMRON.
OMRON MAKES NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED, REGARDING NON-INFRINGEMENT,
MERCHANTABILITY, OR FITNESS FOR PARTICULAR PURPOSE OF THE PRODUCTS. ANY BUYER OR USER
ACKNOWLEDGES THAT THE BUYER OR USER ALONE HAS DETERMINED THAT THE PRODUCTS WILL SUITABLY MEET
THE REQUIREMENTS OF THEIR INTENDED USE. OMRON DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR
IMPLIED.
LIMITATIONS OF LIABILITY
OMRON SHALL NOT BE RESPONSIBLE FOR SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES, LOSS OF PROFITS,
OR COMMERCIAL LOSS IN ANY WAY CONNECTED WITH THE PRODUCTS, WHETHER SUCH CLAIM IS BASED ON
CONTRACT, WARRANTY, NEGLIGENCE, OR STRICT LIABILITY.
In no event shall the responsibility of OMRON for any act exceed the individual price of the product on which liability is asserted.
IN NO EVENT SHALL OMRON BE RESPONSIBLE FOR WARRANTY, REPAIR, OR OTHER CLAIMS REGARDING THE
PRODUCTS UNLESS OMRON'S ANALYSIS CONFIRMS THAT THE PRODUCTS WERE PROPERLY HANDLED, STORED,
INSTALLED, AND MAINTAINED AND NOT SUBJECT TO CONTAMINATION, ABUSE, MISUSE, OR INAPPROPRIATE
MODIFICATION OR REPAIR.
Application Considerations
SUITABILITY FOR USE
OMRON shall not be responsible for conformity with any standards, codes, or regulations that apply to the combination of
products in the customer's application or use of the products.
Take all necessary steps to determine the suitability of the product for the systems, machines, and equipment with which it will
be used.
Know and observe all prohibitions of use applicable to this product.
NEVER USE THE PRODUCTS FOR AN APPLICATION INVOLVING SERIOUS RISK TO LIFE OR PROPERTY WITHOUT
ENSURING THAT THE SYSTEM AS A WHOLE HAS BEEN DESIGNED TO ADDRESS THE RISKS, AND THAT THE OMRON
PRODUCTS ARE PROPERLY RATED AND INSTALLED FOR THE INTENDED USE WITHIN THE OVERALL EQUIPMENT OR
SYSTEM.
Disclaimers
CHANGE IN SPECIFICATIONS
Product specifications and accessories may be changed at any time based on improvements and other reasons. Consult with
your OMRON representative at any time to confirm actual specifications of purchased product.
DIMENSIONS AND WEIGHTS
Dimensions and weights are nominal and are not to be used for manufacturing purposes, even when tolerances are shown.
Related Products
Heater Element Burnout Detector
K2CU
Enables detection of single-phase/three-phase burnouts.
For heaters with ON/OFF control only, provides voltage
fluctuation compensation.
Rated current: 0.25 to 80 A AC
Current Sensor
SAO
Enables detection of single-phase/three-phase overcurrents.
Inverse operation models and instantaneous operation models
(with startup lock) are available.
Rated current: 1 to 160 A AC
For details, refer to the Measuring & Motor Protective Relays Group Catalog (Cat. No. X070).
• The application examples provided in this catalog are for reference only. Check functions and safety of the equipment before use.
• Never use the products for any application requiring special safety requirements, such as nuclear energy control systems, railroad systems, aviation systems, medical equipment,
amusement machines, vehicles, safety equipment, or other application involving serious risk to life or property, without ensuring that the system as a whole has been designed to address
the risks, and that the OMRON products are properly rated and installed for the intended use within the overall equipment or system.
ALL DIMENSIONS SHOWN ARE IN MILLIMETERS.
To convert millimeters into inches, multiply by 0.03937. To convert grams into ounces, multiply by 0.03527.
OMRON Corporation Industrial Automation Company Authorized Distributor:
Tokyo, JAPAN
Contact: www.ia.omron.com
Regional Headquarters
OMRON EUROPE B.V. OMRON ELECTRONICS LLC
Wegalaan 67-69-2132 JD Hoofddorp One Commerce Drive Schaumburg,
The Netherlands IL 60173-5302 U.S.A.
Tel: (31)2356-81-300/Fax: (31)2356-81-388 Tel: (1) 847-843-7900/Fax: (1) 847-843-7787
OMRON ASIA PACIFIC PTE. LTD. OMRON (CHINA) CO., LTD. © OMRON Corporation 2009 All Rights Reserved.
No. 438A Alexandra Road # 05-05/08 (Lobby 2), Room 2211, Bank of China Tower, In the interest of product improvement,
Alexandra Technopark, 200 Yin Cheng Zhong Road, specifications are subject to change without notice.
Singapore 119967 PuDong New Area, Shanghai, 200120, China CSM_9_3_0618 Printed in Japan
Tel: (65) 6835-3011/Fax: (65) 6835-2711 Tel: (86) 21-5037-2222/Fax: (86) 21-5037-2200 Cat. No. N137-E1-03 0508
Mouser Electronics
Authorized Distributor
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K8AC-H21PN-FLK
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