Varistor Products
Thermally Protected
TMOV
™
and
iTMOV
™
Varistor Series
The Littelfuse TMOV and
iTMOV
thermally protected varistors represent a
new development in integrated circuit protection. Both versions are com-
prised of radial leaded MOVs (Metal Oxide Varistors) with an integrated
thermally activated element designed to open in the event of overheating
due to the abnormal overvoltage, limited current, conditions outlined in
UL1449.
The
iTMOV
varistor differs from the TMOV varistor by the inclusion of a
third lead for the purpose of indicating that the MOV has been disconnect-
ed from the circuit. This lead facilitates connection to monitoring circuitry.
The TMOV and
iTMOV
varistors offer quick thermal response due to the
close proximity of the integrated thermal element to the MOV body. The
integrated configuration also offers lower inductance than most discrete
solutions resulting in improved clamping performance to fast over-voltage
transients. Additionally, TMOV and
iTMOV
varistors are wave solderable,
thus simplifying end product assembly by reducing the expense and
rework associated with hand soldering operations.
The TMOV and
iTMOV
varistors are both recognized surge suppression
components to UL 1449. The TMOV and
iTMOV
varistor’s integrated
thermal element, in conjunction with appropriate enclosure design, helps
facilitate TVSS module compliance to UL1449 for both cord connected
and permanently connected applications.
TMOV and
iTMOV
varistors are compatible for use with industry standard
wave-soldering processes or recommended hand-soldering methods.
®
Features
• Patent Pending Integrated Thermal Protection Device
• Designed to facilitate compliance to UL1449 for TVSS product
• High peak surge current rating up to 10kA
• Wave solderable
• Standard lead form and spacing option
• Low Leakage
• -55°C to +85°C Operating Temperature Range
• Third lead for indication purposes.
AGENCY APPROVALS:
Recognized under the components program of
Underwriters Laboratories UL1449. Includes selected tests from UL1020,
regarding thermal cutoffs.
AGENCY FILE NUMBERS:
UL E75961
Applications
• TVSS Products
• AC Panel Protection Modules
• AC Line Power Supplies
• Surge Protected Strip Connectors
• AC Power Meters
• Re-locatable AC Power Taps
24
w w w. l i t t e l f u s e . c o m
Varistor Products
Thermally Protected
TMOV
™
and
iTMOV
™
Varistor Series
TMOV Varistor Series -
Absolute Maximum Ratings
Absolute Maximum Ratings
For ratings of individual members of a series, see Device Ratings and Specifications chart
J
C
C
%/
o
C
V
V
MΩ
o
o
Operating Ambient Temperature Range (TA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to 85
Storage Temperature Range (TSTG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to 125
Temperature Coefficient (αV) of Clamping Voltage (VC) at Specified Test Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . <0.01
Hi-Pot Encapsulation (Isolation Voltage Capability). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2500
Thermal Protection Isolation Voltage Capability (when operated). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 600
Insulation Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,000
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device
at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Device Ratings and Specifications - TMOV Varistor Series
™
MAXIMUM RATING (85°C)
CONTINUOUS
TRANSIENT
PEAK SURGE
SUPPRESSED
VOLTAGE
CURRENT
AC
ENERGY
RATING
8/20µs
VOLTS
2ms
UL 1449
I
TM
I
TM
TABLE 60.1
V
M(AC)RMS
W
TM
1 x PULSE
2 x PULSE
(V)
(J)
(V)
(A)
(A)
115
300
6000
4500
35
115
300
10000
6500
52
130
50
400
6000
4500
130
100
400
10000
6500
140
55
500
6000
4500
140
110
400
10000
6500
150
60
500
6000
4500
150
120
400
10000
6500
175
70
700
6000
4500
175
135
700
10000
6500
230
80
700
6000
4500
230
160
700
10000
6500
250
100
800
6000
4500
250
170
700
10000
6500
275
110
900
6000
4500
275
190
700
10000
6500
320
136
900
6000
4500
320
273
900
10000
6500
150
6000
385
1200
4500
300
10000
385
1200
6500
160
6000
420
1200
4500
320
10000
420
1200
6500
SPECIFICATIONS (25°C)
MAXIMUM
VARISTOR
CLAMPING
VOLTAGE AT 1mA
VOLTAGE
TEST CURRENT
8/20µs
V
N(DC)
V
N(DC)
V
C
I
PK
MIN
MAX
(V)
(V)
(A)
162
198
50
300
162
198
300
100
184
226
340
50
184
226
340
100
200
240
360
50
200
240
360
100
216
264
395
50
216
264
395
100
243
297
455
50
243
297
455
100
324
396
595
50
324
396
595
100
351
429
650
50
351
429
650
100
387
473
710
50
387
473
710
100
459
561
840
50
459
561
840
100
682
558
1025
50
682
558
1025
100
748
612
1120
50
748
612
1120
100
TYPICAL
CAPACI-
TANCE
f = 1MHz
C
(pF)
1100
2400
1000
1900
900
1750
800
1600
700
1400
550
1100
500
1000
450
900
380
750
360
700
300
600
PART
NUMBER
TMOV14R115E
TMOV20R115E
TMOV14R130E
TMOV20R130E
TMOV14R140E
TMOV20R140E
TMOV14R150E
TMOV20R150E
TMOV14R175E
TMOV20R175E
TMOV14R230E
TMOV20R230E
TMOV14R250E
TMOV20R250E
TMOV14R275E
TMOV20R275E
TMOV14R320E
TMOV20R320E
TMOV14R385E
TMOV20R385E
TMOV14R420E
TMOV20R420E
DEVICE
MODEL
NUMBER
BRAND-
ING
4T115E
20T115E
4T130E
20T130E
4T140E
20T140E
4T150E
20T150E
4T175E
20T175E
4T230E
20T230E
4T250E
20T250E
4T275E
20T275E
4T320E
20T320E
4T385E
20T385E
4T420E
20T420E
DISC
DIA-
METER
(mm)
14
20
14
20
14
20
14
20
14
20
14
20
14
20
14
20
14
20
14
20
14
20
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25
VARISTOR
PRODUCTS
Continuous:
TMOV Varistor
Steady State Applied Voltage:
AC Voltage Range (VM(AC)RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 to 420
Transient:
Peak Pulse Current (ITM)
For 8x20µs Current Wave, single pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6000 to 10,000
Single-Pulse Energy Capability
For 2ms Current Wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 to 320
UNITS
V
2
A
Varistor Products
Thermally Protected
TMOV
™
and
iTMOV
™
Varistor Series
iTMOV
Varistor Series -
Absolute Maximum Ratings
Continuous:
Steady State Applied Voltage:
AC Voltage Range (VM(AC)RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 to 420
Transient:
Pulse Peak Current (ITM)
For 8/20µs Current Wave, Single Pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10,000
Single-Pulse Energy Capability
For 10/1000µs Current Wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 to 320
Operating Ambient Temperature Range (TA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to 85
Storage Temperature Range (TSTG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to 125
Temperature Coefficient (αV) of Clamping Voltage (VC) at Specified Test Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . <0.01
Hi-Pot Encapsulation (Isolation Voltage Capability). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2500
Isolation Voltage Capability (When Thermal Element Has Opened) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 600
Insulation Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000
Indicator Lead Rating (Lead-3):
Continuous RMS current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Surge Current, 8/20µs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10,000
V
Absolute Maximum Ratings
iTMOV
Varistor
UNITS
A
J
C
C
%/
o
C
V
(AC)
V
(AC)
MΩ
o
o
mA
A
Device Ratings and Specifications -
iTMOV
Varistor Series
MAXIMUM RATING (85°C)
CONTINUOUS
TRANSIENT
MINIMUM
PEAK SURGE
SUPPRESSED
CURRENT
RMS
ENERGY
VOLTAGE
8/20µs
VOLTS
2ms
RATING
UL 1449
I
TM
I
TM
TABLE 60.1
V
M(AC)
W
TM
1 x PULSE 2 x PULSE
(V)
(V)
(J)
(A)
(A)
115
300
52
10000
6500
130
400
100
10000
6500
140
400
110
10000
6500
150
400
120
10000
6500
175
700
135
10000
6500
230
700
160
10000
6500
250
700
170
10000
6500
275
700
190
10000
6500
320
900
273
10000
6500
385
1200
300
10000
6500
420
1200
320
10000
6500
SPECIFICATIONS (25°C)
MAXIMUM
VARISTOR
CLAMPING
VOLTAGE AT 1mA
VOLTAGE
TEST CURRENT
8/20µs
V
N(DC)
V
N(DC)
V
C
I
PK
MIN
MAX
(V)
(V)
(A)
162
198
300
100
184
226
340
100
200
240
360
100
216
264
395
100
243
297
455
100
324
396
595
100
351
429
650
100
387
473
710
100
459
561
840
100
558
682
1025
100
612
748
1120
100
TYPICAL
CAPACI-
TANCE
f = 1MHz
C
(pF)
2400
1900
1750
1600
1400
1100
1000
900
750
700
600
PART
NUMBER
TMOV20R115M
TMOV20R130M
TMOV20R140M
TMOV20R150M
TMOV20R175M
TMOV20R230M
TMOV20R250M
TMOV20R275M
TMOV20R320M
TMOV20R385M
TMOV20R420M
DEVICE
MODEL
NUMBER
BRAND-
ING
20T115M
20T130M
20T140M
20T150M
20T175M
20T230M
20T250M
20T275M
20T320M
20T385M
20T420M
DISC
DIA-
METER
(mm)
20
20
20
20
20
20
20
20
20
20
20
26
w w w. l i t t e l f u s e . c o m
Varistor Products
Thermally Protected
TMOV
™
and
iTMOV
™
Varistor Series
Lead Configurations
TMOV Varistor
Thermal
Fuse
Element
iTMOV
Varistor
2
Thermal
Fuse
Element
3
2
VARISTOR
PRODUCTS
TO STATUS
ANNUNCIATOR
LIGHT/ALARM
Monitor Lead
MOV
MOV
1
2
3
1
Note: MOVs are non-polarized passive elements
iTMOV
Varistor Application Examples
The application examples below show how the indicator lead on the
iTMOV
can be used to indicate that the thermal element has been
opened. This signifies that the circuit is no longer protected from
transients by the MOV.
Line
Line Fuse
To Protected Circuit
AC OPTOCOUPLER
Load Switch Relay
(loss of protection)
"Load Powered"
neon lamp
R
iTMOV
Varistor
LED
Application Example 1 (Figure 1)
In this case, the LED is normally on, and is off when the thermal
element opens.
R
Neutral
Figure 1. Application example 1
Application Example 2 (Figure 2)
This circuit utilizes an optocoupler to provide galvanic isolations
between the
iTMOV
varistor and the indicating or alarm circuitry.
Application Example 3 (Figure 3)
This circuit illustrates the use of the monitoring lead of the
iTMOV
varistor to ensure that equipment is only operated when overvoltage
protection present. In normal operation the load switch relay solenoid is
powered via the indicator lead of the
iTMOV
varistor. In the event of the
thermal element being activated, the relay will deactivate, cutting power
to the protected circuit and the fault LED will illuminate.
Line
To Protected Circuit
Line Fuse
iTMOV
Varistor
R
Neutral
Figure 2. Application example 2
Please note: Indicator circuits are provided as a guideline only.
Verification of actual indicator circuitry is the responsibility of the end
user. Component values selected must be appropriate for the specific
AC line voltage service and application.
Line
Line Fuse
iTMOV
Varistor
Fault LED
(Normallyoff)
Neutral
Figure 3. Application example 3
w w w. l i t t e l f u s e . c o m
27
To Protected Circuit
Varistor Products
Thermally Protected
TMOV
™
and
iTMOV
™
Varistor Series
Thermal Characteristics
10
100
Typical
PERCENT OF RATED VALUE
Limited
Current
(A)
5A
2.5A
0.5A
0.125A
80
1
60
40
20
0.1
10
100
Time s
1000
10000
0
-55
50
60
70
80
90
100
AMBIENT TEMPERATURE (ºC)
110
120
130
* Figure 4: Typical time to open circuit under UL1449
Abnormal Overvoltage Limited Current Test
Figure 5: Peak Current & Energy Derating Curve
Note : The TMOV and
iTMOV
varistors are intended, in conjunction with
appropriate enclosure design, to help facilitate TVSS module compliance
to UL 1449, Section 37.4 (abnormal overvoltage limited current require-
ments). Under these extreme abnormal overvoltage conditions, the units
will exhibit substantial heating and potential venting prior to opening.
Modules should be designed to contain this possibility. Application testing
is strongly recommended.
For applications exceeding 85ºC ambient
temperature, the peak surge current and energy
ratings must be reduced as shown in Figure 3.
Transient V-I Characteristic Curves
14mm
10000
Maximum Clamping Voltage
Maximum Leakage Current
Maximum Leakage Current
20mm
10000
Maximum Clamping Voltage
Clamping Voltage (V)
Clamping Voltage (V)
1000
420V
385V
320V
275V
250V
230V
1000
420V
385V
320V
275V
250V
230V
175V
150V
140V
130V
115V
175V
150V
140V
130V
115V
100
0.000001 0.00001 0.0001 0.001 0.01
0.1
1
10
100
1000 10000
100
0.000001 0.00001 0.0001 0.001 0.01
0.1
1
10
100
1000 10000
Peak Current (A)
Peak Current (A)
Figure 6: V-I Characteristic Curves for 14mm Types
Figure 7: V-I Characteristic Curves for 20mm Types
Pulse Rating Curves
10000
2
1000
Peak Current (A)
1
10000
10
10
2
1
2
10
10
2
Model 14 mm
10
3
Model 20 mm
10
3
10
4
10
5
1000
Peak Current (A)
10
4
10
5
10
6
10
6
100
100
∞
10
∞
10
1
10
100
Impulse Duration (µs)
1000
10000
1
10
100
Impulse Duration (µs)
1000
10000
Figure 8: Pulse Rating Curves for 14mm types
28
Figure 9: Pulse Rating Curves for 20mm types
w w w. l i t t e l f u s e . c o m