Series-CMT200

Supported Applications

The Dwyer Series CMT200 Carbon Monoxide Transmitter is designed to monitor gas concentration in underground parking garages, vehicle maintenance facilities, and mechanical rooms. The unit provides a field-selectable output proportional to the detected carbon monoxide (CO) levels.

Operating Conditions & Performance

The Series CMT200 utilizes a field-replaceable electrochemical sensor with a typical lifespan of 4 years and an output drift of less than 5% per year in air. The measurement range is fixed at 0 to 200 PPM, covering areas typically between 5000 to 7000 sq. ft.

Performance specifications include:

• Accuracy: ±2% of reading at the time of calibration
• Response Time: <45 s to 90% of final value
• Ambient Temperature Limits: -4 to 122°F (-20 to 50°C)
• Humidity Limits: 15 to 90% RH constant; 0 to 99% RH intermittent
• Storage Temperature: For best sensor life, 32 to 68°F (0 to 20°C)

The device is housed in UV resistant polycarbonate and carries CE approval.

Configuration Options

The series offers configurable output signals and housing styles to accommodate different installation requirements. Calibration is performed using onboard span and zero adjustment potentiometers (15 turn).

• Housing Options: Round housing or Rectangular housing (-R suffix)
• Output Signals: Jumper selectable 4-20 mA (loop powered) or 2-10 V
• Power Requirements: Current output: 18-28 VDC; Voltage output: 18-28 VDC/VAC, reverse polarity protected
• Electrical Connection: Removable terminal block with two PG11 and one PG 16 knockouts for conduit fitting
• Load Requirements: For voltage output, load must be >50 KΩ. For current output, the load must not exceed maximum loop resistance calculated as Rmax = (Vps - 18) / 20 mA.

Available accessories include Model A-507A calibration adapter, Model GCK-200CO-2000CO2 calibration gas, and Model A-GSTA-SE security enclosure. The replacement carbon monoxide sensor is available as part number A-505.

Key Product Differences

The Series CMT200 distinguishes between two primary housing configurations:

• CMT200 (Round Housing): Features a diameter of 3-9/64 in [79.781 mm] and height of 1-37/64 in [39.891 mm]. Mounting thread is Ø1-5/64 in [27.317 mm].
• CMT200-R (Rectangular Housing): Features a width of 4-17/32 in [115.09 mm], height of 5-7/64 in [129.78 mm], and depth of 3-1/8 in [79.38 mm]. Includes a knockout size of 3-45/64 in [94.06 mm].

Both configurations share the same sensor technology, measurement range, accuracy, response time, and electrical specifications.