CARBON MONOXIDE TRANSMITTERSCMT Series
INTRODUCTIONINSTALLATIONINSTRUCTIONSWARNING

Thank you for choosing an HK Instruments CMT series carbon
monoxide transmitter. CMT is an easy-to-use, reliable transmitterfor detecting CO gas. It is commonly used to control ventilation inareas where high concentrations of CO may cause serious healthproblems.
The recommended transmitter calibration interval is one year.

APPLICATIONS
CMT devices are commonly used in places where air includes CO gas
emissions, such as:• Commercial parking garages• Apartment garages• Tunnels and terminals• Car and bus maintenance garages• Warehouses and factories• Car service centers• READ THESE INSTRUCTIONS CAREFULLY BEFOREATTEMPTING TO INSTALL, OPERATE OR SERVICE THIS
DEVICE.
• Failure to observe safety information and comply withinstructions can result in PERSONAL INJURY, DEATH AND/OR
PROPERTY DAMAGE.
• To avoid electrical shock or damage to equipment, disconnect
power before installing or servicing and use only wiring withinsulation rated for full device operating voltage.
• To avoid potential fire and/or explosion do not use in potentiallyflammable or explosive atmospheres.
• Retain these instructions for future reference.
• This product, when installed, will be part of an engineered
system whose specifications and performance characteristics
are not designed or controlled by HK Instruments. Review
applications and national and local codes to assure that theinstallation will be functional and safe. Use only experienced andknowledgeable technicians to install this device.

SPECIFICATIONSSPECIFICATIONS
Performance

Measurement range:
0...300 ppm CO
Linearity:≤2 % on 300 ppm CO
Cross sensitivity:≤2 % on 300 ppm CO
Reproducibility:≤3 ppmTechnical Specifications

Response time:<60 sGas entry:
by diffusion
Measuring element:
Electro-chemical
Environment:
Operating temperature: -10...40 °C
Humidity: 15 to 95 % rH

Physical

Case:
Dimensions: 90 x 95 x 36 mm
Weight: 87 g
Materials:
Case: ABS
Lid: PC
Protection standard:
IP54
Electrical connections:2-pole screw terminal, max 1.5 mm2
Cable entry:
M16

Conformance

Safety for sensor:
TÜV-approval according to VDI 2053
R.F.I according to EN 50 081-1 resp. EN 50 082-2 B
Meets the requirements for CE marking:
EMC Directive: 2014/30/EU
RoHS Directive: 2011/96/EU
WEEE Directive: 2012/19/EU

Electrical

Supply voltage:
14...28 VDC
Output signal:
4...20 mA, maximum load 300 Ω

COMPANY WITH
MANAGEMENT SYSTEMCERTIFIED BY DNV GL= ISO 9001 = ISO 14001 =Copyright HK Instruments 2019www.hkinstruments.fi

RoHS 2
2011/65/EU

Installation version 5.0 2019

STEP 2: WIRING DIAGRAMSDIMENSIONAL DRAWINGS90

For CE compliance, a properly grounded shielding cable is required.
1) Unscrew the strain relief and route the cable(s).
2) Connect the wires as shown in figure 2.
3) Tighten the strain relief.

36779553

71.5

Figure 2 - Wiring diagram

Power supply
14...28 VDC+A

4–20 mA
4–20 mAO
4.3

INSTALLATIONRECYCLING/DISPOSAL

1) Mount the device in the desired location (see step 1).
Recommended mounting height is 1.5…1.8 m above the floor.
2) Open the lid and route the cable through the strain relief andconnect the wires to the terminal block(s) (see step 2).
3) The device is now ready to be used.

The parts left over from installation should berecycled according to your local instructions.
Decommissioned devices should be taken to a
recycling site that specializes in electronic waste.  WARNING! Apply power only after the device is properly wired.

STEP 1: MOUNTING THE DEVICEWARRANTY POLICY

1) Select the mounting location. Recommended mounting
height is 1.5…1.8 m above the floor. Recommended
mounting height is 1.5…1.8 m above the floor.
2) Use the device as a template and mark the screw holes.
3) Mount with appropriate screws.

The seller is obligated to provide a warranty of five years for the delivered goods regarding material and manufacturing. The warranty period
is considered to start on the delivery date of the product. If a defectin raw materials or a production flaw is found, the seller is obligated,when the product is sent to the seller without delay or before expiration of the warranty, to amend the mistake at his/her discretion either
by repairing the defective product or by delivering free of charge to thebuyer a new flawless product and sending it to the buyer. Delivery costs
for the repair under warranty will be paid by the buyer and the return
costs by the seller. The warranty does not comprise damages caused byaccident, lightning, flood or other natural phenomenon, normal wear
and tear, improper or careless handling, abnormal use, overloading, improper storage, incorrect care or reconstruction, or changes and installation work not done by the seller or his/her authorized representative.
The selection of materials for devices prone to corrosion is the buyer’sresponsibility, unless otherwise is legally agreed upon. Should the manufacturer alter the structure of the device, the seller is not obligated tomake comparable changes to devices already purchased. Appealing forwarranty requires that the buyer has correctly fulfilled his/her duties
arisen from the delivery and stated in the contract. The seller will givea new warranty for goods that have been replaced or repaired within
the warranty, however only to the expiration of the original product’s
warranty time. The warranty includes the repair of a defective part ordevice, or if needed, a new part or device, but not installation or exchange costs. Under no circumstance is the seller liable for damages
compensation for indirect damage.

Figure 1a - Surface mounting

Figure 1b - Mounting orientation

YES

Copyright HK Instruments 2019

NONO

www.hkinstruments.fi

Installation version 5.0 2019