ENMET MX-52 - Manual (Page 17)

MX52 C ONTROL ENMET Corporation
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5.2.2 Light-emitting diodes (LED) (Figure 10)
Each channel is equipped with five LEDs, when are visible and identified on the FRONT panel.
LED Extinguished Illuminated steady mode Flashing
GREEN Channel not in service Channel in service Channel in service
1st red AL1 not triggered Threshold AL1 exceeded
(automatic clearing)
Threshold AL1 exceeded
(manual clearing)
2nd red AL2 not triggered Threshold AL2 exceeded
(automatic clearing)
Threshold AL2 exceeded
(manual clearing)
3rd red AL3 not triggered Threshold AL3 exceeded by
mean or time
(automatic clearing)
Threshold AL3 exceeded by
mean or time
(automatic clearing)
Yellow No fault Fault on channel - Channel being calibrated or
programmed
- Detector being calibrated
5.2.3 Alarm Thresholds
Each of the three alarm thresholds can be programmed independently for each channel. (See the “Channel
programming” menu).
In normal operation, a gas alarm is only triggered after a preprogrammed time delay in order to avoid spurious alarms.
Alarm thresholds can be processed in the following manners:
In normal cycle with manual clearing: block diagram 1.
In normal cycle with automatic clearing: block diagram 2.
In parking cycle: block diagram 3.
The alarm thresholds are to be selected according to the gases detected and the corresponding standards in force.
T = Time of 5 seconds or alarm 3 time delay
START
No Yes
Yes Yes
Alarm acknowledged
No
Alarm acknowledged
No
LED extinguished
Relay disengaged
Buzzer stopped
Yes
LED steady mode
Buzzer stopped
Yes
END
Threshold exceeded
Illumination of
flashing alarm LED
Time T exceeded
Relay engaged
Buzzer engaged
Alarm LED
extinguished
Block Diagram 1: Normal Cycle with Manual Clearing
No
Illumination of
flashing alarm LED
After T2 time