For more information & Technical support:
24
F-Guard UV-IR User Manual
Doc. No. F110V0020.06
3.6
Enable dirty window warning 0-20mA
If enabled, this feature assists predictive maintenance by indicating an alert when the BIT signal is
reduced by 75% of the value needed to trigger a BIT fault failure. When activated, the milliampere
output will drop to 3mA and the LED will remain steady green, it should be noted that a fire signal
will override the dirty window warning. A process variable of optical contamination (BIT signal level)
is
accessible via HART and/or MODBUS. The value of the field ranges from 0 (clean) to 100% (BIT
fault).
3.7
Auxiliary Relay
The Aux relay can be set to operate in parallel to the alarm relay, at pre-alarm level, when high
IR or high UV energy is present or on “dirty window warning.
3.8
Window Heater
The detector is equipped with a heater to prevent condensation and icing on the window. If enabled,
the heater is operated automatically depending on temperature.
3.9
Modbus Address
The detector can communicate with the “FGD communicator” software using a Modbus RTU
compatible protocol on RS-485. This protocol allows for a network of detectors to be connected,
each with a unique Modbus address. The address of the detector can be set to any value in the range
1–247.
3.10
Manual BIT – Alarm Output Test (Full loop test)
When enabled, the alarm outputs are activated when a
Manual
BIT is initiated. See section 4.2 –
“Testing” for details.
WARNING
Make sure to disable all fire extinguishing actions or alarms connected to the detector when the
manual BIT is initiated and the “Manual BIT – Alarm Output Test” is enabled as the Manual BIT will
set the 0-20mA terminal to 20mA and close the alarm relay and auxiliary relay if configured.