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Supervised Alarm / Relay / Power Expansion Unit
Expansion Unit Power Supply Fuse
A 4-ampere (4A) fast-blow fuse mounted on the lower part of
the power supply circuit board, provides protection to the
power supply from high-energy surges. If this fuse faults fre-
quently, consider adding a UL-1449-Listed power-line surge
protection device.
WARNING
Verify that the main AC power to the Expansion
Unit cabinet is switched OFF and locked against
accidental starting.
1) Turn OFF the main circuit breaker controlling power to
the Expansion Unit cabinet.
2) Pull the insulating fishpaper cover away from the power
supply.
3) Using a non-conducting fuse puller, remove the old fuse
(see Figure 16).
4) Replace the fuse with a 5x20mm, 4-Amp, 250V, fast-blow
(not a time-lag) fuse.
5) Reset the main circuit breaker.
Expansion Unit Accessory Circuit Protection
A 3.0 Amp resetable fuse protects the battery
charger circuit, and a 2.5 Amp resetable fuse lim-
its the output to the accessory circuits to safe lev-
els. These devices limit the accessory current
even when the product is operating under backup
power from the battery.
Under conditions of moderate overloads, the power supply will
shut down its output, but periodically power-up briefly to test
to determine if the overload is removed. This will be visible
because the PWR Lamp will flash on about once per second.
Power will be restored immediately upon removal of the over-
load condition.
CIRCUIT PROTECTION
Figure 15 - Expansion Unit Power Supply Fuse Location
Figure 16 - Power Supply Fuse Location
5x20mm
4A/250V Fuse
"Fish Paper"
Cover
