MULTIPLEX
Atmospheric Oil Mist Detection System
AM8/JANUARY 2015
EMAIL [email protected] WEBSITE www.oilmist.com 4 East Barnet Road, London, England, EN4 8RW TEL +44 (0)20 7328 3121
Fault Finding
Part4-4
FAULT
ACTION
REMEDY
F4 on display
Mains power to the Junction
Box has failed or has been
turned off
Check that there is mains power getting
to the Junction Box
Fuse on the PSU in the
Junction Box has blown
Replace the fuse with a 3.15A fuse from
the spares kit. (Q0115)
Fuse on the PSU in the
Junction Box has blown again
If the fuse blows again, the PSU has
failed and is faulty. Order a replacement
PSU
Bad connection between
Monitor and Junction Box (in
the multi-twisted pair cable)
1. If the PSU is working, remove the
mains power to the Junction Box
2. Connect a piece of wire between
terminals 29 and 30 on the Junction
Box PCB
3. Leaving the mains power
disconnected to the Junction Box,
reset the Monitor
4. If F4 has now gone, the cable from
the Monitor to the Junction Box is
okay
5. Remove the links from terminal 29
and 30
Bad connection on RED and
BLACK wires from PSU to
AUX conn and – on
Junction Box PCB
With the power connected to the
Junction Box, using a meter when the
PSU is working, check that there is a
shorted connection between terminals 29
and 30 on the Junction Box PCB
If there is an open circuit, it could mean
that the red and black wires between the
PSU and the PCB have a bad connection
or the relay has failed
Relay on the Junction Box
PCB has failed
If the connection is sound, the relay
could be faulty. Order a new Junction
Box PCB
Fault alarm
comes on. QMI
Monitor shuts
down and
display ceases
Check FS4 fuse on side of
Monitor above security key
3.15A anti-surge fuse may have blown
due to an internal fault in the Monitor.
Check FS4 (Q0115) fuse in the Monitor.
NOTE
: Monitors are ex-stock QMI
