Sierra Monitor 4501-XX User Manual

The Model 4501-XX Series Toxic Gas 2-wire
gas sensor modules allow easy direct
connection to many DCS, PLC and other
control devices. The sensor module is best in
class for ease of installation, reliable operation,
ease of use, and, with 180 day calibration cycle,
low cost of operation.

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.

4501-03 Oxygen, O
4501-04 Carbon Monoxide, CO

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Toxic Gas Sensor Module

2-Wire Series 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).

4501-05 Hydrogen Sulfide, H2S
4501-06 Chlorine, Cl
4501-08 Chlorine Dioxide, ClO
4501-10 Sulfur Dioxide, SO
4501-12 Nitrogen Dioxide, NO
4501-25 Ammonia, NH
4501-26 Hydrogen Fluoride, HF

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Explosion proof all models

FM Performance Approval for 4501-05

Model 4501 Series Sensors

Sierra Monitor Corporation 1991 Tarob Ct. Milpitas, CA 95035 USA [phone] [phone] Fax: [phone]

Visit our website: www .sierramonitor.com E-mail: [e-mail]

2-Wire Toxic Gas Sensor Module Model 4501-XX

Specifications:

Performance Max. Gas Ran ge (1) Resolution Respo nse Time (2) Sensor Life
4501-03 O2 0 - 25% Vol 0.2% Vol. <10 Seconds 20 Months
4501-04 CO 0 - 1200 PPM 0.5 PPM <25 Seconds 2 Years
4501-05 H2S 0 - 100 PP M 0.1 PPM <30 Seconds 2 Years
4501-06 Cl2 0 - 10 PP M 0.1 PPM <60 Seconds 2 Years
4501-08 ClO 2 0 - 3 PPM 0.1 PPM <60 Seconds 2 Years
4501-10 SO2 0 - 100 PPM 0.5 PPM <20 Seconds 2 Years
4501-12 NO2 0 - 20 PP M 0.2 PP M <35 Seconds 2 Years
4501- 25 NH 3 0 - 100 PPM 1.0 PP M <30 Seconds (3)
4501- 26 HF 0 - 10 PPM 1.0 PP M <90 Seconds (3)

Output:

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

(Trouble: 3.6 mA)

Loop Resistance 800 ohm

Electrical Data:

Power consumption: 0.2 watts
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: -4o to 122 oF(-20o to 50 oC)

4501-25/26 +14o to 113 oF(-10o to 45 oC)

Extended Temp: Sensor and 4-20 mA will continue to

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)
Storage Temp: -4o to 122 oF(-20o to 50 oC)
Relative Humidity:
Standard: 15-90%
4501-25/26: 20-90%

Construction:

Dimensions: 7.0 x 3.6 x 4.0 in. (H x W x D)

(17.8 x 9.1 x 11.2 cm.)

4501-25/26 8.4 x 4.4 x 3.9 in. (H x W x D)

(21.3 x 11.2 x 9.9 cm.)

Weight: 2.2 lb. (1.0 Kg) Al

4.6 lb. (2.1 Kg) SS

4501-25/26 3.0 lb. (1.3 Kg) Al

5.0 lb. (2.3 Kg) SS

Enclosure: Aluminum, Stainless S teel

Approvals and Warranty:

Hazardous Location: Explosion proof, NEMA 4X
FM: Class I, Div. I, Group s B, C, D

Class II, Div. I, Groups E, F, G

CSA: Class I, Div. I, Group s B, C, D

Class II, Div. I, Groups E, F, G

4501-05 FM Performance Approval:

4501-05 Approval FM ISA-92.0.01,
Part I-1998 and FM 3600

Limited warranty: 2 years

Specifications subject to change without notice

(1) Other ranges available
(2) To 90% range
(3) Ammonia and HF sensor

requires electrolyte recharge
up to year

Ordering
Information:

Model - Gas - Enclosure

4501 Series - 03 = O

- 04 = CO - A2 = Aluminum Enclosure, M20 x 1.5

- A1 = Aluminum Enclosure, 3/4” NPT

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- 05 = H2S - S1 = Stainless Steel Enclosure, 3/4” NPT

- 06 = Cl

- 08 = ClO

- 10 = SO

- 12 = NO

- 25 = NH

- 26 = HF

High Capacity Calibration Accessories

1250-01 Gas Sensor Calibration Kit, Type A (CO, H2S)
1250-02 Gas Sensor Calibration Kit, Type B (SO2, NO2)
1250-03 Gas Sensor Calibration Kit, Type C (Cl
1260-00 Gas Cylinder, Air (Type A) 105 liters
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

- S2 = Stainless Steel Enclosure, M20 x 1.5

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Accessories

5311-00 Rainshield
5311-02 Rainshield with calibration port

2,

ClO2)

Calibration Accessories

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

Tool, 4501-XX

1260-10 Gas Cylinder, Sulfur Dioxide, 50 ppm, Type B
1260-12 Gas Cylinder, Nitrogen Dioxide, 10 ppm, Type B
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, NH
SPX 27057 Kit, Sensor Recharge, for 4501-25

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Sierra Monitor Corporation 1991 Tarob Ct. Milpitas, CA 95035 USA [phone] [phone] Fax: [phone]

Visit our website: www.sierramonitor.com E-mail: [e-mail]

Rev. 5/2012