Sierra Monitor Corporation 4501-XX User Manual

The Model 4501-XX Series T oxic Gas 2-wire gas
sensor modules allow easy direct connection to
many DCS, PLC and other control devices. The
sensor module, in a stainless steel enclosure, is
best in class for ease of installation, reliable
operation and ease of use.

The 4501-XX Gas Sensor Module utilizes the electro­chemical cell to monitor for the specified gas over vari­ous gas specific ranges. This compact Module requires
minimal maintenance. Internal continuous self-diagnos­tics will automatically indicate any fault problems. The
4501-XX is best in class providing all the built-in fea­tures desired by instrumentation and safety profession­als, including:

• Industry’s longest calibration interval of 180 days

• 2-wire loop powered for easy installation and

direct interface to common PLC and DCS

• Integral scrolling LCD 2-line, 16 character dis­play

• Non-intrusive one-person calibration

• 316 Stainless S teel or aluminum enclosure

• 4-20 mA output

• Long sensor life

• Robust RFI immunity

• Ability to rotate face plate to enable the enclo-

sure to be mounted in any orientation.

Toxic Gas Sensor Module

2-Wire

Model 4501-XX

How It Works

Electrochemical sensors are fuel cell-like devices con­sisting of an anode, cathode, and electrolyte. The com­ponents of the cell are selected so a subject gas, al­lowed to diffuse into the cell, will cause a chemical re­action and generate a current. The cells are diffusion
limited so the rate the gas enters the cell is solely de­pendent on the gas concentration. The current gener­ated is proportional to the rate of consumption of the
subject gas in the cell.

Sierra Monitor electrochemical sensors provide improved
reliability by allowing the gas to diffuse into the sensor
through a capillary port, rather than diffusing through
membranes. The result is an extremely stable sensor
with very low temperature and pressure coefficients and
the capability to monitor gas as ppm (toxics).

4501-04 Carbon Monoxide, CO
4501-05 Hydrogen Sulfide, H2S
4501-06 Chlorine, Cl
4501-08 Chlorine Dioxide, ClO
4501-25 Ammonia, NH

Model 4501 Series Sensors

Sierra Monitor Corp. 1991 Tarob Court Milpitas, CA 95035 USA [phone] [phone] Fax: [phone]

Visit our website: www.sierramonitor .com E-mail: sales@sierramonitor .com

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Explosion proof all models

FM Performance Approval for 4501-05

Specifications:

2-Wire Toxic Gas Sensor Module Model 4501-XX

Performance 4501-04

Max. Range (1) 0-1200 PPM
Resolution 0.5 PPM
Response Time (2) <25 sec.
Sensor Life 2 years

(1) Other ranges available
(2) To 90% range
(3) Ammonia sensor requires electrolyte recharge
up to 1 year

4501-05

0-100 PPM

0.1 PPM
<30 sec.
2 years

Output:

Display: Scrolling LCD, 2-line, 16-characters
Signal Output: 2-wire sensor powered analog 4-20 mA

Loop Resistance 800 ohm

(Trouble: 3.6 mA)

Electrical Data:

Power consumption: <160 milliwatts
Connection type: 2-wire, loop-powered
Input voltage: 24 VDC nominal: 14-30VDC
RFI/EMI Protection: EN50081-2, EN50082-2

Operating Range:

Ambient T emp Range:

Standard: See Table below
Extended T emp Sensor and 4-20 mA will continue to

Storage Temp: -4o to 122 oF(-20o to 50oC)

operate to -40oF (-40oC) but the LCD
display will decay over time if exposed
to temperatures below -4o (-20o C) for
significant time (not for 4501-25)

4501-06

0-10 PPM

0.1 PPM
<60 sec
2 years

4501-08

0-3 PPM

0.1 PPM
<60 sec
2 years

4501-25

0-100 PPM

1.0 PPM
<30 sec
(3)

Construction:

Dimensions: 7.0 x 3.6 x 4.0 inches (H x W x D)
4501-25 12,6 x 3,6 x 4.0 inches

Weight: 4.4 lb. (2.0 Kg)
4501-25 5.0 lb. (2.3 Kg)

Enclosure: Stainless S teel, NEMA 4X
Remote Sensor
Option: 4501-04 Max 25 feet

4501-05 Max 25 feet
4501-06 Max 15 feet

(17.8 x 9.1 x 11.2 cm)

Approvals and Warranty:

FM Approval: Explosion proof, Enclosure

4501-05 Approval FM Performance Approval Standards:

Limited warranty: 2 years

Class 1, Div. I, Group s B, C, D
Class 2, Groups B, C, D
Class 1, Zone 1, Group IIB+H2 IP66

4501-05 Approval FM ISA-92.0.01, Part I­1998 and FM 3600

Specifications subject to change without notice

4501-04 CO

Ambient T emp (oF) -4 to 122 oF
Ambient T emp (oC) -20 to 50 oC
Relative Humidity 5 – 99%

4501-05 Hl2S

-40 to 122 oF

-40 to 50 oC
5 – 99%

4501-06 Cl

-4 to 122 oF

-20 to 50 oC
5 – 99%

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Ordering Information

4501-04-AL Sensor Module, 2-Wire, Carbon Monoxide, CO, Aluminum Enclosure
4501-04-SS Sensor Module, 2-Wire, Carbon Monoxide, CO, 316 SS Enclosure
4501-05-AL Sensor Module, 2-Wire, Hydrogen Sulfide, H2S, Aluminum Enclosure
4501-05-SS Sensor Module, 2-Wire, Hydrogen Sulfide, H2S, 316 SS Enclosure
4501-06-AL Sensor Module, 2-Wire, Chlorine, Cl2, Aluminum Enclosure
4501-06-SS Sensor Module, 2-Wire, Chlorine, Cl2, 316 SS Enclosure
4501-25-AL Sensor Module, 2-wire, Ammonia, NH3, Aluminum Enclosure
4501-25-SS Sensor Module, 2-wire, Ammonia, NH3, SS Enclosure
4501-51 Remote sensor assembly, 4501 Series

Calibration Accessories

5358-01 Calibration Adapter, Standard
5360-00 Calibration Gas Delivery Fitting
5358-51 Calibration/Configuration Magnetic Tool,

4501-XX

Remote Sensor Distances

4501-01 25 feet
4501-05 25 feet
4501-06 15 feet
4501-08 15 feet

High Capacity Calibration Accessories

1250-01 Gas Sensor Calibration Kit, Type A (CO and H2S)
1250-03 Gas Sensor Calibration Kit, Type C (Chlorine)
1260-04 Gas Cylinder, Carbon Monoxide, 100 ppm, Type A
1260-05 Gas Cylinder, H2S in N2, 25 ppm Type A
1260-06 Gas Cylinder, Chlorine, 5 ppm, Type C
1260-13 Gas Cylinder, Carbon Monoxide, 1000 ppm, Type A
1260-45 Gas Cylinder, H2S in N2, 10 ppm, Type A
9210-00 Calibrator, Permeation tube
9211-09 Permeation Tube, Ammonia, NH3

4501-25 15 feet

4501-08 ClO

-4 to 122 oF

-20 to -50 oC
5-95%

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4501-25 NH

-14 to 113 oF

-10 to 45 oC
20-95%

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Sierra Monitor Corp. 1991 Tarob Court Milpitas, CA 95035 USA [phone] [phone] Fax: [phone]

Visit our website: www.sierramonitor .com E-mail: sales@sierramonitor .com

Rev. C 10/02/08