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INSTALLATION GUIDE - REMOTE ACCESS CONTROLLER RAC 4XT • PK3191_10_14
5.7 Power Failure
In the event of an electrical failure the RAC 
4XT system will recover its configuration 
automatically if power is restored within 3 
days.
When electrical power is restored after a 
power failure, verify the status of the LED D41 
on the controller PCB. If the LED is OFF use an 
initialization card with the reader and perform 
a time reset on the RAC 4XT as per the FDU 
or ATLAS manuals.
NOTE:  When the power to the RAC 4XT is 
too low (power failure, low voltage in 
battery back-up) the controller PCB 
stops functioning and the relays on 
the controller PCB or the expansion 
board will return to their normal state. 
Any peripheral connected to the relays 
will then be either in a normally open 
(NO) or normally closed (NC) state, 
dependent on the wiring.
5.8 Loading Recommendations
CAUTION:
 Do not exceed the load limitations of the 
RAC 4XT system.
The maximum recommended load for all 
output relays in the RAC 4XT system is 1 Amp 
at 30 VDC. The tamper switch rating is 1 Amp 
at 30 VDC.
The current supplied by the controller PCB is 
for the locking device used is 0.75 Amps from 
connector J18, pin 1. Refer to Annex A, Table 
3.
5.9 System Deactivation
In order to deactivate the RAC 4XT system, 
disconnect both terminals from the battery 
back-up (if equipped), then disconnect the 
AC power either by removing the power 
adaptor from the wall outlet, or by shutting 
off the main power to the electrical outlet the 
system is connected to.
!