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58000081 Iss 01
9. Fault detection and LEDs
The air curtain monitors the fan speed,
power output and heatsink temperature. In
the event of a fault the red LED on the sec-
ondary PCB flashes:
The red LED flashes a number of times and
then pauses. The number of flashes de-
notes the fault.
When the air curtains are powered up in
standby mode, a green LED on the main
board shows that the 12V power supply is
working correctly:
When heat or cold blow is demanded the
secondary PCBs are powered. A second
LED on the main PCB shows that the second
12V power supply is working correctly:
A fault with the auxiliary power is indicated
by a flashing orange LED on the main PCB:
A green LED on the secondary PCBs shows
that they are receiving 12V power:
Number
of flashes
Fault
1
Power measurement when triacs
switched off:
Response: Auto run motor
2
Motor fault
Response: Disable heating
3
Triac heatsink overheat:
Response: Reduce heating
4
Low power measurement when
triacs switched on:
Causes: Thermal cutout tripped,
blown fuse, missing phase
Main PCB
Main PCB
Main PCB
Secondary PCB
Secondary PCB