Sensors, Sentry gas sensor modules – Sierra Monitor Corporation Sentry 5100 Series User Manual
Page 2

SENSORS
Electrochemical
Electrochemical sensors are fuel cell-like devices consist-
ing of an anode, cathode, and electrolyte. The compo-
nents of the cell are se-
lected so a subject gas
allowed to diffuse into the
cell will cause a chemical
reaction and generate a
current. The cells are dif-
fusion limited, so the rate
at which the gas enters
the cell is solely depen-
dent on the gas concentration. The current generated is
proportional to the rate of consumption of gas in the cell.
Unlike other electrochemical sensors where gas diffuses
through membranes into the cell, Sierra Monitor sensors
allow gas to diffuse into the sensor through a simple cap-
illary. The result is an extremely stable sensor with very
low temperature and pressure coefficients.
Common Specifications for All 5100 Series Sensors
Communication to Controller: SentryBus PSG
Zero Drift:
Less than 5% per year
Calibration Frequency:
90 Days Recommended
Transmission:
Digital – RFI, EMI immune
Warranty:
2 years
Housing:
Explosion proof (NEMA 7)
(Div. 1, Class 1, Groups C,D)
Optional upgrade to Group B,
NEMA 4X
Dimension:
7.6 X 4.6 X 4.2 inches
(19.3 X 11.7 X 10.7 cm)
Note that 5100-26 is larger
Weight:
2.7 lb. (1.3 Kg)
GAS SENSOR SPECIFICATIONS
Gas
Model
Sensor
Range
Time
Sensor
Operating
Relative
Number
Type
Response
Life
Temperature
Humidity
Carbon Monoxide
5100-16
Electrochem 0-2,000 PPM
90% <35 sec. 2 yr.
4
o
to 122
o
F (-20
o
to 50
o
C)
15-99% RH
(Hydrogen Tolerant to
2,000 PPM H2)
Nitric Oxide
5100-19
Electrochem 0-20 PPM
90% <15 sec. 3 yr.
4
o
to 122
o
F (-20
o
to 50
o
C)
15-99% RH
Hydrogen Cyanide
5100-22
Electrochem 0-20 PPM
90% <70 sec. 2 yr.
4
o
to 122
o
F (-20
o
to 50
o
C)
15-99% RH
Ethylene Oxide
5100-27
Electrochem 0-20 PPM
90% <90 sec. 2 yr.
4
o
to 122
o
F (-20
o
to 50
o
C)
15-99% RH
Sierra Monitor Corp. 1991 Tarob Ct., Milpitas, CA 95035, USA, 408-262-6611, 800-727-4377, FAX: 408-262-9042
Web Site: http://www.sierramonitor.com E-Mail: [email protected]
© 2013 by Sierra Monitor Corporation
Sentry
Gas Sensor Modules