Sierra Monitor Corporation Sentry 5100 Series User manual

Two types of gas sensor modules are available for
the Sentry Gas Risk Management System. For
the more common gases such as Combustible
Gas, Oxygen, Carbon Monoxide, Hydrogen Sul-
fide, Chlorine and Ammonia, Sierra Monitor offers
the IT Series Smart Gas Sensor Modules. More
information on the IT Series is available in the spe-
cific IT Series data sheets. For other gases Sierra
Monitor offers the 5100 Series Gas Sensor Mod-
ules described in this data sheet.
SierraMonitortoxicgassensormodulesutilizeelec-
trochemical technology to achieve the most accu-
rate and reliable monitoring of gas concentration.
All Sentry 5100 Series sensor modules easily in-
terface to the Sentry controller. Each module has
a unique address, which allows signals from mul-
tiple modules to be multiplexed for communication
with the controller on the same cable. All Sierra
Monitor gas sensor modules are designed for hos-
tile or hazardous environments and are in enclo-
sures approved for Div. 1, Class 1, Groups C, D
locations.
SENTRYFEATURESINCLUDE:
Digital Signal Transmission Serial communication to
the controller enables multiplexing sensor modules on a
signalcable,significantlyreducinginstallation costs. This
assuresRFIand EMIimmunityoverextended distances.
One-Person, Non-intrusive Calibration Inthecalibra-
tion mode, sensors continue to monitor for hazardous
conditionsuntilcalibration gasisapplied. All adjustments
aremadeautomatically aftercalibrationgas hasbeenre-
moved. Sentrynotifiestheoperatorofcalibration comple-
tion and allows acceptance or rejection of the calibration
at the controller keypad. There are no manual adjust-
mentsrequired at the sensor module.
Low Sensitivity Check Automatic, post-calibration
checkof sensor for proper output. Lowsensitivity alpha-
numericmessagewarnsofneedforsensormaintenance.
Power Up & Calibration Delays Atstart-upor calibra-
tion the output of the sensor is locked out and remains
lockedforfive minutes to avoiderroneousreadingsduring
thewarm-upperiod andaftercalibration.
Diagnostic Information The alphanumeric display on
the Sentry Controller provides easy to understand diag-
nostic messages.
Sierra Monitor Corp. 1991 Tarob Ct., Milpitas, CA95035, USA, 408-262-6611, 800-727-4377, FAX: [phone]
Web Site: http://www.sierramonitor.com E-Mail: [e-mail]
©2009by SierraMonitorCorporation
Sentry
Gas Sensor Modules

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
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)
Note1: Diffusionviamembrane
GASSENSOR SPECIFICATIONS
Gas Model Sensor Range Time Sensor Operating Relative
Number Type Response Life Temperature Humidity
Hydrogen 5100-07 Electrochem 0-1,000 PPM 90% <30 sec. 2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Sulfur Dioxide 5100-10 Electrochem 0-100 PPM 90% <20 sec. 2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Nitrogen Dioxide 5100-12 Electrochem 0-20 PPM 90% <35 sec. 2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Carbon Monoxide 5100-13 Electrochem 0-1,000 PPM 90% <25 sec. 3yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Carbon Monoxide 5100-16 Electrochem 0-2,000 PPM 90% <35 sec. 2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
(Hydrogen Tolerant to
2,000 PPM H2)
Nitric Oxide 5100-19 Electrochem 0-20 PPM 90% <15 sec. 3yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Hydrogen Chloride 5100-21 Electrochem 0-20 PPM 90% <100 sec.2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Hydrogen Cyanide 5100-22 Electrochem 0-20 PPM 90% <70 sec. 2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Hydrogen Fluoride 5100-26 Electrochem10-10 PPM 90% <30 sec. 1yr. 14o to 113o F(-10o to 45o C) 20-95% RH
Ethylene Oxide 5100-27 Electrochem 0-20 PPM 90% <90 sec. 2yr. 4o to 122o F (-20o to 50o C) 15-99% RH
Sierra Monitor Corp. 1991 Tarob Ct., Milpitas, CA95035, USA, 408-262-6611, 800-727-4377, FAX: [phone]
Web Site: http://www.sierramonitor.com E-Mail: [e-mail]
©2009by SierraMonitorCorporation
Sentry
Gas Sensor Modules