Tyco 4100U - Manual (Page 157)

D-2
Review the guidelines below before initiating an Earth Fault Search.
• The Detect Earth Fault jumper must be installed at each SPS, RPS, TPS, IPS, or
4009T for earth fault detection to occur.
• Only one power supply per location is configured to detect earth faults.
• For more reliable earth fault searching:
- Use a Firefighter Telephone NAC for each telephone riser connection to
a transponder.
- Use IDNet channel isolators to isolate channel faults to a specific
segment of channel wiring.
- Set IDNet channel isolator addresses to the lowest IDNet device
addresses, increasing with communication distance from the IDNet
card.
• If an earth fault is suspected on the IDNet channel with multiple isolators, start
an IDNet Channel Search before doing a Location Search. If the Location Search
is done first, it may not yield the correct location (this is a by-product of the
extended amount of time required for the IDNet channel to initialize during a
Location Search). Note: The 4009 IDNet NAC Extender has a common ground
fault trouble that reports to the panel without running the Earth Fault Search.
• Earth Fault Search detects only one fault at a time. Multiple faults require fixing
the first fault and then repeating the search.
• The FACP suspends normal operation for the duration of the Earth Fault Search.
• Location Earth Fault Searches optionally allow exclusion of auxiliary power
circuits from the search, so that modules connected to the 24 V auxiliary outputs
can remain in operation during the search.
• The option to exclude auxiliary power circuits does not apply to IDNet devices,
because the entire IDNet communication channel is isolated during each search.
• During the search, all related troubles are suppressed and a single trouble
pseudo-point is activated (P438).
• At the completion of the search, all slaves are restarted and normal panel
operation resumes.
• Earth Fault Search is only supported by new 4100U modules. 4100 Legacy (slot
format) modules are not supported, with the following exceptions:
-
MAPNET channel isolation during location search
- IPS for earth fault detection (not recommended). The Earth Fault
Search may fail because the isolation circuits of some 4100U slaves
(such as the 4100U telephone slave) do not support IPS.
IMPORTANT: The fire panel cannot provide fire protection during an Earth
Fault Search.
General Guidelines