Common Installation/Operation Mistakes
Proportional Output Connected Incorrectly
The proportional output uses a red wire for the positive analog output and a green wire for the
reference analog ground. Reversing these connections will result in inaccurate readings or no
readings at all.
Setting the Proportional Output Incorrectly
If the controller connected to the proportional output is expecting a certain output signal, the
jumpers on JP2 and JP3 must be configured to output that type of signal. A common mistake
is leaving JP2 set to mA while moving JP3 to the desired voltage output. This causes the unit
to read between 12 and 15 VDC with the output not changing proportional to the sensor’s gas
readings.
Using Improper Resistance/Impedance
If using the 4-20 mA current loop mode, the resistance of the cable connecting the output to
the controller must be less than 250 Ω. If using one of the voltage modes, the input impedance
of the controller must be greater than 100 kΩ. If these requirements are not adhered to, the
proportional output will not accurately reflect the concentration of gas measured by the sensor.
Transmitter Mounted in an Unsatisfactory Location
For reliable operation, the transmitter(s) must be mounted in the proper locations. Please read
“Mounting the Transmitter” on page 12 for guidelines on choosing locations.
Common mistakes include mounting a transmitter too close to a garage door. When the door
is open, rain may blow through the doorway and onto the transmitter housing. Another
common mistake is to mount the transmitter in a location where it comes in direct contact with
engine exhaust. The large amount of contaminates in engine exhaust can shorten the useful
life of the sensor.
One more common mistake is to choose a mounting location that places the transmitter too
near the outlet of air conditioners or heaters. Quick, drastic changes in ambient temperature
can cause erratic shifts in the transmitter readings.
By following the mounting guidelines, many of the problems caused by improper mounting
locations can be eliminated.
IOM02
Rev 1.0 – December 22, 2020
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