Table 2-3: Functions
(continued)
Function
Setting
Auxiliary relay
•
Yes: Activate auxiliary relay at warning level.
•
No: Activate auxiliary relay at alarm level (default).
Automatic BIT
•
Yes: Perform automatic and manual built-in test
(default).
•
No: Perform manual built-in test only.
Alarm BIT
•
Yes: Successful manual built-in test activates the
alarm relay for approximately three seconds (default).
•
No: Successful manual built-in test does not activate
the alarm relay.
•
Yes: Successful manual built-in test activates the
auxiliary relay for approximately three seconds
(default).
•
No: Successful manual built-in test does not activate
the auxiliary relay.
(1)
Only available in output configurations 1R and 2R.
2.8.5
Heated optics
To configure optical window heating, select one of the modes listed below.
•
OFF: Optical window surface heating does not operate.
•
ON: Optical window surface heating operates continuously.
•
AUTO: Optical window surface heating operates according to temperature change.
Specify the start temperature below which the optical window surface is heated to
improve performance in temperatures where snow, ice, and condensation may occur.
In AUTO mode, the default Heat On setting is 41 °F (5 °C). Heating stops when the
temperature is 27 °F (15 °C) above the start temperature.
You can define the start temperature below which the window will be heated. The
temperature can be defined between 32 and 122 °F (0 and 50 °C).
Reference Manual
Installing the detector
00809-0100-4975
August 2019
Rosemount 975MR
37
