SN90RC-4
- 4 Analog Channel, Battery Powered Wireless Sensor Node
- 2 RTD Inputs and 2 Current Transformer Inputs Plus 2 Switch Inputs
- Supports 2- and 3-Wire 100 ohm Platinum RTDs
- True RMS Current Measurement
- Switch State and Change-of-State Monitoring
- Non-volatile Data Logging Memory
- Robust 900 MHz FHSS DNT90 Radio
- Internal Antenna or External 2 dBi Antenna Options
- Optional 128-Bit AES Encryption
- Compatible with LG90E and LG90C Gateways
- Configuration Over-the-Air or Through the Serial Port
- Up to 5 Years of Battery Life
- FCC and Canadian IC Certified for Unlicensed Operation
The SN90RC-4 is a battery-powered wireless sensor node that provides support for
two 100 ohm Platinum RTD inputs, two current transformer inputs and two switch
inputs (many other sensor configurations are available, contact
Murata
for details).
Connectivity is provided through a 900 MHz Frequency Hopping Spread Spectrum
(FHSS) wireless connection, making use of the companion LG90E Ethernet gate-
way or LG90C cellular gateway. The unique low-power architecture used in the
SN90RC-4 provides years of battery operation. Sensor data and battery status are
automatically transmitted based on user-configurable conditions, simplifying appli-
cation software design. The wireless sensor node can be configured over-the-air or
through its serial port.
4-Channel
RTD/CT
Wireless
Sensor
Node
SN90RC-4 Specifications
Characteristic
Sensor Inputs
RTD Type
RTD Temperature Range
RTD Resolution
RTD Accuracy
RTD Measurement Data Format
Input Range for Current Transformer
Current Measurement Resolution
Current Measurement Accuracy
Current Measurement Data Format
Open Contact Voltage
Closed Contact Current
Contact Status Data Format
16-bit Unsigned Value
3.3
33
8-bit Unsigned Value
V
µA
0
16
±2
Sym
Notes
Minimum
Typical
Maximum
Units
2- or 3-wire 100 ohm Platinum RTDs
Current Transformers
Contact Closures
100 ohm Platinum, 0.00385 Alpha
-200
0.0625
±0.3
16-bit Signed Value
3.34
mA
RMS
bits
%
+600
o
o
o
C
C
C
Copyright © Murata Manufacturing Co.,
N.A.,
All Rights Reserved 2010
©2010-2015 by Murata Electronics
Ltd.
Inc.
SN90RC-4 (R) 04/17/15
1 of 5
www.murata.com
SN90RC-4 Specifications
Characteristic
Internal Battery Voltage Range
Internal Battery Voltage Accuracy
Internal Battery Voltage Data Format
Serial Interface
Radio
Operating Frequency Range
RF Data Rate
Number of RF Channels
RF Transmit Power, EIRP, Chip Antenna
RF Transmit Power, EIRP, 2 dBi Antenna
Receiver Sensitivity, 10E-5 BER:
Internal Antenna
Optional External Antenna
Supplied Battery
Operating LTC Battery Life, -40 to +85
o
C:
1 Minute Report Interval
15 Minute Report Interval
1 Hour Report Interval
Optional Battery
Operating Alkaline Battery Life, -20 to +50
o
C:
1 Minute Report Interval
15 Minute Report Interval
1 Hour Report Interval
Report Triggers:
Timer
Measurement Value
Switch Input
Operating Temperature Range
Operating Humidity Range, Non-condensing
Nominal Dimensions
Mounting
100 ms to > 1 year
High and Low Measurement Thresholds
(channels are individually programmable)
Switch Opening Event, Switch Closing Event,
or Both Events
-40
5
5.5 x 2.5 x 1.3 inches
140 x 64 x 33 mm
Left and Right Flanges, Two Pre-drilled Holes
Plus Slot in Each Flange
+85
95
o
Sym
Notes
Minimum
3.0
Typical
Maximum
3.6
±2
Units
V
%
16-bit Unsigned Value
RS232C, 38.4 kbps, 8N1,
no flow control
Murata
DNT90 FHSS Radio
902.76
100
25, 26 or 52
40 or 158
63 or 250
-100
SMD Chip Antenna
2 dBi RPSMA Dipole Antenna
Lithium Thionyl Chloride (LTC) C Cell, 8.5 A-hr
mW
mW
dBm
927.24
MHz
kbps
1.5
5
5
3 Alkaline AA Cells, 2.5 A-hr
years
years
years
0.4
2+
3+
years
years
years
C
%RH
Copyright © Murata Manufacturing Co.,
N.A.,
All Rights Reserved 2010
©2010-2015 by Murata Electronics
Ltd.
Inc.
SN90RC-4 (R) 04/17/15
2 of 5
www.murata.com
+
J 1
2 /3 -W ir e
R T D # 1
2
3
J 2
1
2
3
J 3
C u rre
X fo rm e r # 1
I p u s
2
3
J
C u rre
X fo rm e r # 2
I p u s
2
3
J
C o
a c
# 1
2
J 6
C o
a c
# 2
2
J 7
H o s
H o s
T X
1
2
3
R X
1
1
1
C u rre
S h u
1
C u rre
S h u
1
S N 9 0 R C -4 B lo c k D ia g r a m
M o d e
C o
ro l
S w i c h e s
+
+
L i k S a u s &
A c i i y L E D s
2 /3 -W ir e
R T D # 2
B a
M o
e ry
i o r
S e s o r
M e a s u re m e
S y s e m
µ C o
r o lle r
D N T 9 0
F H S S
R a d io
+
R S 2 3 2 C
C o
e r e r
Figure 1
SN90RC-4 Operation
The SN90RC-4 is a 900 MHz FHSS-based wireless
sensor node that supports two 100 ohm platinum RTD
inputs, two current transformer inputs and two switch
closure inputs. The SN90RC-4 includes internal stor-
age for more than 1500 time-stamped sets of read-
ings, where each set includes the four analog
channels and the two switch inputs. The SN90RC-4’s
very low average power consumption provides up to
five years of operation from a 8.5 A-hr C cell LTC bat-
tery. Alternately, the SN90RC-4 can be powered from
three inexpensive AA batteries in limited temperature
range applications where shorter battery operating life
is acceptable.
The SN90RC-4 wireless sensor node is available with
either an internal antenna or an external 2 dBi dipole
antenna.
The SN90RC-4 includes two LED indicators and two
buttons to facilitate installation, activation, configura-
tion and testing.
As shown in Figure 1, J1 and J2 provide connection
points for 2- or 3-wire RTDs. J3 and J4 provide con-
nection points for current transformer inputs. J5 and
J6 provide connection points for contact status
inputs, with J7 providing connection points for 3-wire
RS232 communication with a host computer.
The SN90RC-4 automatically reports the sensor
input readings on user-defined intervals and condi-
tions, eliminating the need for application polling.
When the SN90RC-4 sends data, it wakes up, syn-
chronizes with its gateway, transmits the data and
quickly returns to sleep, maximizing battery life.
The internal battery voltage is included in each sensor
report, providing continual information on the battery
status. The SN90RC-4 can be configured over-the-air,
or through its serial port using a standard 3-wire
RS-232 connection.
Copyright © Murata Manufacturing Co.,
N.A.,
All Rights Reserved 2010
©2010-2015 by Murata Electronics
Ltd.
Inc.
SN90RC-4 (R) 04/17/15
3 of 5
www.murata.com
Connector J1 and J2 Description, 2- or 3-Wire RTD Input
Pin
1
2
3
Name
RTD+
RTD-
RTD-/GND
I/O
I
I
I
Description
3-wire RTD positive (red) input. This input is connected to the RTD current source and the ADC positive differ-
ential input.
First 3-wire RTD negative (black) input. This input is connected to the ADC negative differential input. This in-
put is not used with a 2-wire RTD.
Second 3-wire RTD negative (black) input or 2-wire RTD negative input. This input is connected to the RTD
ground return.
Connector J3 and J4 Description, Current Transformer Input
Ref
1
2
3
Name
CURRENT 1
CURRENT 2
GND
I/O
I
I
-
Description
First current transformer input. There is a 300 ohm current shunt between this terminal and terminal 2.
Second current transformer input.
Ground terminal.
Connector J5 and J6 Description, Contact Input
Ref
1
2
Name
CONTACT
GND
I/O
I
-
Description
Contact input. This terminal is connected to +3.3 V through a 100 K resistor.
Contact ground terminal.
Connector J7 Description, 3-Wire RS232
Ref
1
2
3
Name
HOST TX
HOST RX
GND
I/O
I
O
-
Input terminal for host RS232 TX.
Output terminal for host RS232 RX.
RS232 ground terminal.
Description
Copyright © Murata Manufacturing Co.,
N.A.,
All Rights Reserved 2010
©2010-2015 by Murata Electronics
Ltd.
Inc.
SN90RC-4 (R) 04/17/15
4 of 5
www.murata.com
S N 9 0 R C -4 C a s e D im e
5 .5
(1 4 0 )
5 .0
(1 2 7 )
s io
s
2 .5
(6 4 )
1 .6 5
(4 2 )
0 .1 1
(3 .0
0 .3 3
(8 .5
5
8
)
)
0 .2
0 .3
# 6
(M
(5
5 (
- #
3 .5
.0 ) D ia
9 .0 ) a
8 S c re
- M 4 .5
w
T h ru
8 2 D e g
S c re w )
1 .3
(3 3 )
D im e
s io
s i
i c h e s a
d (m m )
Figure 2
Note: Specifications subject to change without notice.
Copyright © Murata Manufacturing Co.,
N.A.,
All Rights Reserved 2010
©2010-2015 by Murata Electronics
Ltd.
Inc.
SN90RC-4 (R) 04/17/15
5 of 5
www.murata.com
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
