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2 built-in-test (bit) – Spectrex 40/40R - Single IR Flame Detector User Manual

Page 26

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SharpEye

TM

Single IR Flame Detector User Guide

14

Internal Detector Tests

• Processor Watch dog
• Software
• Memory
• Oscillator frequency
Response to Fault Indication
If a failure is found, the detector indicates by:
• Fault relay:

• Opens in wiring option 1, 2, and 4
• Closes in wiring option 3 and 5

• 0-20mA: indicates Fault (0mA or 2mA) in wiring option 1, 2, 3
• LED – Yellow flashes (4 Hz)
• Correcting the Fault
The fault indications remain until the detector’s power is removed. The fault

indications return if the fault is still found when power is restored.

1.6.2 Built-In-Test

(BIT)

The detector’s Built-In-Test (BIT) also checks the following:
• Electronics circuitry
• Sensors
• Window cleanliness
The detector can be set to perform the BIT in the following modes:
• Automatically and manually
• Manually only
Note: In Manual BIT, the outputs may also be tested and Control System
‘inhibit’ should be applied if this could initiate other systems.

1.6.2.1

How the BIT Operates

• The detector's status remains unchanged if the result of a BIT is the

same as the current status (NORMAL or BIT Fault)

• the detectors’ status is changed (from Normal to BIT Fault or vice versa)

if the BIT differs from the current status

Note: In ‘BIT Fault’ status the detector can continue to detect a fire.