The 5100-02-IT Combustible Gas Sensor Module is
a key member of the powerful Sierra Monitor IT
Series family of gas sensor modules. The 5100-02-
IT provides the features needed by safety and
instrumentation engineers including:
180 day calibration interval
FM Approval for performance and safety
Modbus RTU RS-485 interface
4-20 mA output
SMC Sentry digital bus interface
Optional Integral and Trouble alarm relays
Aluminum or 316 Stainless Steel enclosure
Integral scrolling LED display
Optional remote sensor
Remote alarm reset capable
Model 5100-02-IT utilizes the proven, reliable,
catalytic bead technology to monitor for combustible
gases (methane and others). Output range is 0-
100% of Lower Explosive Limit (LEL). This detector
has minimal maintenance requirements and is
Factory Mutual approved for six month calibration
intervals. Internal, continuous self-diagnostics
automatically detect and alarm any fault problems.
The 5100-02-IT can be used as a 4-20 mA
component or as a Modbus RTU node. For higher
level system capability the module can interface
directly to Sierra Monitors Sentry Controller
enabling system level Modbus serial
communications, area and zone alarm
management, extensive system diagnostic features,
WebServer interface, and multiplexing sensor
Factory Mutual (FM) Approval for performance,
electrical safety and environmental parameters
including Class I, Div. 1, Groups B, C, D and Class
I, Zone 1, Group IIC, IP66. With a NEMA-4X
enclosure standard, approved multiplexing, and
approved six month calibration interval, cost of
ownership is minimized at the acquisition,
installation and operating stages
How It Works
Catalytic Bead gas sensors detect gas by
comparing the resistance of two heated elements.
One element is catalytic to enhance the burning of
combustible gases, the other element is passive.
Electronic circuits are used to compare the change
in the catalytic bead resistance relative to the
passive bead. The relative change is calibrated to
determine the concentration of the gas of interest.
Sensor type: Catalytic Bead.
Repeatability: +/-1% LEL.
Response Time: T60<10sec
Calibration freq: 180 days.
Accuracy: +/- 1% for 0-50% LEL range
+/- 2% for 51-100% LEL range.
Display: Fixed and Scrolling LED.
Signal Output: Sentry digital bus.
Analog 4-20 mA.
Serial RS-485 Modbus RTU.
Relay : Optional.
Relays: 5 amp Alarm, Warning (0.25 amp Trouble)
5A@ 250 VAC, 5A@ 30VDC (Alarm, Warning).
Board includes auxiliary connection for Sentry
HART: Termination board includes HART, Modbus RS-
485, 4-20mA, Digital Input, 2A Relay output, No
Power consumption: 3 watts max.
Input voltage: 24 VDC nominal: 10-30VDC.
RFI/EMI Protection: EN50081-2, EN50082-2.
Ambient Temp Range: -40o to 176oF (-40o to 80oC).
Relative Humidity: 0-99% Non-Condensing.
Dimensions: (H x W x D)
(A1 & A2) 6.9 x 5.7 x 3.9 in. (17.5 x 14.5 x 9.9 cm)
(S1 & S2) 7.5 x 5.0 x 4.4 in. (19 x 13 x 11 cm)
(A1 & A2) 3.4 lb. (1.5 Kg)
(S1 & S2) 7.2 lb. (3.3 Kg)
Housing: Epoxy coated Aluminum or 316 Stainless Steel
Classification: Explosion proof, Class I, Div. 1,
Groups B, C, D Class I, Zone 1,
Group IIC, IP66, IP65, NEMA 4X.
II2 GD, Ex d IIC T6 = -40oC to 85oC.
Warranty: 2 years
FM Approval 6320 Combustible Gas Detector Performance.
FM Approval 3600 Class I Div. 1, Groups B, C, D.
SIL-2 Certified Certified by Lloyd's Register (IEC 61508).
ATEX Certified II 2G, Ex d IIB + H2 T5 Gb.
CE Marked Certificate of Approval.
CSA For enclosure in hazardous locations.
ABS Certificate of Compliance.
CQST Certificate for China.