Spectrex 20/20MU - Mini Flame Detector - Manual (Page 22)

Spectrex Inc. - SharpEye TM ML & MU Flame Detector Manual – TM 767100, Rev. A, April 2005
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4.2 Output Signals
The detector provides the following outputs:
• Alarm relay
• Fault relay
• 4-20mA current output
• RS-485 communication
The detector can be in one of the following states.
Normal:
The detector is functioning normally.
BIT: The detector performs a Built In Test.
Warning: Fire detected – warming alarm (pre-alarm) state
Alarm: Fire detected – fire alarm state
Latched Alarm
(Optional) The alarm outputs are latched due to the detection of a fire
that has already been extinguished.
BIT Fault: A fault is detected during BIT sequence. The detector will
continue to detect fire if the alarm conditions occur.
Fault: A fault is detected when the power supply is too low or
during a software fault.
In each state, the detector will activate different outputs as specified in table 4.
Table 4: Output Signals versus Detector State
Detector
State Color LED Flashing
LED
Alarm
Relay
Fault Relay 4-20mA
Output
Normal Green 1 Hz Off On 4 mA
Warning Red 2 Hz Off On 16 mA
Alarm
(1)
Red Steady On On 20 mA
Latch
(2)
Red Steady On On 20 mA
BIT Fault
(3)
Yellow 4 Hz Off Off 2 mA
Warning at
BIT Fault Red 2 Hz Off Off 16 mA
Alarm at
BIT Fault Red Steady On Off 20 mA
Fault Yellow 4 Hz Off Off 0 mA
Notes:
1 The alarm outputs will be activated as long as the alarm conditions are present
2 The Alarm state can be latched (optional) according to programmable function
3 The detector will be in its BIT FAULT state until it has passed a successful BIT
and will stop approximately 3 seconds after the fire is no longer detected.