Continuous Optical Path Monitoring (COPM)

COPM does a check of the device's optical path (from the internal UV and IR detectors through an air gap then the optical window) and related electronic circuitry every 2 minutes. If the optical window is blocked by unwanted objects such as ice, dirt, or debris for two consecutive checks, the device activates the following Fault output:

•

2.0 mA signal

•

Fault relay de-energizes

•

Modbus signal

After a COPM Fault occurs, COPM occurs every 30 seconds until the Fault condition is removed. When the Fault condition is removed, COPM continues every 2 minutes.

Because COPM does a check of the optical path every 2 minutes and two consecutive checks must fail before a Fault occurs, it can be up to 3 minutes before the device identifies a blockage.

Refer to Cleaning the Optical Window and Reflectors for maintenance instructions.