Emerson Rosemount 975HR, Справочное руководство

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• Sensors
• Window cleanliness
The detector can be set to perform the built-in test in the following modes:
• Automatically and manually
• Manually only
NOTICE
In a manual built-in test, the outputs may also be tested; apply control system inhibit if
this could initiate other systems.
How the built-in test operates
• The detector's status remains unchanged if the result of a built-in test is the same as
the current status (Normal or BIT Fault).
• The detector's status is changed (from Normal to BIT Fault or vice versa) if the built-in
test differs from the current status.
NOTICE
In BIT Fault status, the detector can continue to detect a fire.
Automatic built-in test
The detector automatically performs a built-in test every fifteen minutes. A successful
built-in test sequence does not activate any indicator.
All outputs of built-in test results function as described in Table 1-9 and Table 1-10 , and
the built-in test is automatically executed every one minute.
This continues until a successful built-in test occurs, when the detector resumes normal
operation.
Table 1-9: Results of a Successful Built-in Test
Output Result
Fault relay • Output configurations 1A, 2A, and 1R:
remain CLOSED
• Output configurations 3A and 2R: remain
OPEN
0-20 mA output Output configurations 1A, 2A, and 3A: Normal
(4 mA)
Power LED Green, flashing, 1 Hz on (Normal)
Introduction Reference Manual
June 2021 00809-0100-4976
26 Emerson.com/Rosemount
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