Spectrex 20/20L (LB) - UV/IR Flame Detector - Manual (Page 24)

Spectrex Inc. - SharpEye TM UV/IR Flame Detector Manual – TM20/20LB Rev E, August 2004
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The detector remains in Fault state until it passed a successful BIT. When SW1-4
is OFF, warning state is the same as the Alarm state. The alarm outputs are
activated as long as the alarm conditions are present and stop approximately five
seconds after the fire is no longer detected.
4.5 Built-In-Test (refer to 2.5)
a. Principles
The detector’s Built In Test (BIT) checks the following:
• Electric circuitry
• Sensor
• Window cleanliness
The detector can be set to perform the BIT automatically and manually
(SW1-2 = ON) or manually only (SW1-2 = OFF).
b. Principles
If the BIT succeeds, the detector’s status turns to Normal.
If the BIT fails, a second BIT is executed after a delay of 6 seconds.
If the second BIT succeeds, the detector’s status turns to Normal; otherwise the
status is turned to Fault.
c. Manual BIT only (SW1-2= OFF):
The BIT is initiated manually by momentarily connecting terminal No. 3 with
terminal No. 2.
A successful manual BIT activates the following:
• Fault Relay is closed.
• Alarm Relay is activated for 3 seconds (only if SW1-6 = ON).
• Accessory Relay is activated for 3 sec (only if SW1-7 = ON).
• 4-20mA Output current will be 20mA (only if SW1-6 = ON) or 16mA
(Only if SW1-7 = ON and SW1-6 = OFF).
• The yellow LED blinks at 0.5Hz rate.
Unsuccessful BIT activates the following:
• Fault Relay is released.
• 4-20mA output indicates Fault condition (2mA).
• The yellow LED blink (at 2Hz rate)
Important Note!
If SW1 switches 7 or 6 are in their “ON” position the Alarm and
Accessory Relays will be activated during a MANUAL BIT, therefore,
automatic extinguishing systems or any external devices that may be
activated during BIT must be disconnected.