iPECS-MG Hardware Description and Installation Manual
Issue 1.1
KSU Installation
August, 2010
23
4.6.2 External Backup Battery Installation
In case of power failure, the external backup batteries automatically maintain uninterrupted power for
the iPECS-MG System. The external batteries must provide 24V DC; this is generally accomplished
by connecting two 12V batteries in a series arrangement as shown:
connect the backup battery cable with 2 identical batteries (12V DC)
insert a fuse between the batteries as shown
connect the external back up battery cable to the battery connector of the PSU
after connecting the external backup battery cable, turn on the battery switch
Figure 4.6.2-1 External Backup Battery Installation
NOTE
ㅡ
the cable used to connect the battery is supplied with the KSU.
Battery operation is controlled by the PSU. The PSU will provide charging current to the batteries
during normal AC power operation at a maximum of about 1 Amp. PSU battery operation will be
halted if the AC power is re-connected or if the battery voltage is too low to maintain full-system
operation.
The length of time that the System will operate on the batteries is dependent on several elements
including, battery charge, condition of the batteries, capacity of the batteries, and the size of the
system (number of station ports). The chart below gives the approximate back-up times for several
system sizes and different battery capacities in ampere-hours.
Battery Capacities
BATTERY CAPACITY
DKT 24 PORTS
DKT 72 PORTS
DKT 120 PORTS
20AH
6 hours
3 hours
1.5 Hours
40AH
12 hours
6 hours
3 hours
CAUTION
It is recommended to use an external backup battery fuse between the battery and the System.
The battery must supply 24 VDC with a recommended capacity of 20 Amp-hours
Carefully check the battery polarity with cable colors (Red and Blue) when connecting the battery to
the System.
Do not short out the external batteries and cables.
There is a danger of explosion if external batteries are incorrectly replaced. Replace only with the
same or equivalent type recommended by the manufacturer. Dispose of used batteries according
to the manufacturer’s instructions.