Installation manual

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SIMPLEX Fault Assistance Guide RevA
29 April 2009
If you find that all the bays have been checked, and the earth fault appears to be in the main
CPU Bay, the Earth fault will most likely be in either the integrated IDNet Loop card found on
the power supply, OR, on the Auxiliary fuse distribution board. The loop card can be tested as
per any other loop card. The Auxiliary fuse board should be totally disconnected from the PSU
(power supply unit). If the Earth fault disappears, then the fault lies in the PSU, otherwise you
will need to individually disconnect each of the 24V power supplies from the reconnected Fuse
Distribution Board in turn, narrowing the circuit with the Earth Fault.
For more information on the specifics of 4100U Earth Fault Diagnostics, please refer to the
4100U Installation Manual (LT0350) that was supplied with the panel.
PLEASE NOTE – Intermittent Earth Faults can only be diagnosed whilst the fault is active.
Pre-4100U Series Fire Panels (4100+, 4100A) – The older Simplex 4100 Series Fire panels
have the ability to detect Positive/Negative Earth Ground Faults. Unlike the 4100U Series Fire
panels, their Power Supplies do not have the option to automatically diagnose on which circuit
the fault is located. There are, however, methods which can narrow down the circuits in
question.
To begin, when the Earth fault is currently active on the fire panel:
 Disconnect the power to the different bays (sequentially, and one at a time) until the
Earth Fault clears from the system (NOTE – the Earth Fault may latch on the panel and
may require resetting to effectively test the circuit).
 After locating which bay of cards holds the problem, you will need to disconnect
individual cards using the same methodology.
 Once the card in question is located, you will need to test the circuits but keep in mind
the fault may be with the card, but is more likely is out in the field.
 When the earth fault is located on a Mapnet or IDNet loop, disconnect one end of the
loop from the Loop card (both + and - terminals), and break the loop in different areas
(i.e. line isolators for example) until the Earth Fault disappears.
NOTE
– It is possible for Earth Ground Faults to switch from Positive to Negative Earth Ground
Faults (or Vice-Versa), so when disconnecting circuits it is highly recommended that you
remove BOTH the positive and negative connections for efficient diagnosis.
If you find that all the bays have been checked, and the earth fault appears to be in the main
CPU Bay, the Earth fault will most likely be on the Auxiliary Fuse Distribution Board. The
Auxiliary fuse board should be totally disconnected from the PSU (power supply unit). If the
Earth fault disappears, then the fault lies in the PSU, otherwise you will need to individually
disconnect each of the 24V power supplies from the reconnected Fuse Distribution Board in
turn, narrowing the circuit with the Earth Fault.
PLEASE NOTE – Intermittent Earth Faults can only be diagnosed whilst the fault is active.