Samsung NX-828, Technical Manual

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6.5 Power Failure Transfer
When the system loses AC power, the first two loop start lines in the KSU are automatically
switched to the related single line telephones.
The first and second trunk lines are respectively transferred to the 11th and 12th stations which
are connected to the single line telephone.
6.6 External Battery
The system can continue full operation during AC power failure. This requires that a 24V battery
supply be connected to the bottom of the KSU (Figure 2-24).
When AC power drops below 88V/176 VAC, the system switches over to batteries immediately.
Calls in progress will not be interrupted.
To supply 24 volts, use two 12V batteries or four 6V batteries connected in series. Any Ni-Cd
battery can be used if its rating is not more than 26AH and not less than 6AH. The system will
not operate in power failure mode if battery voltage drops below 21.5 VDC.
NX-828
HYBRID KEY SYSTEM
INSTALLATION
Figure 2-24 Connecting External Batteries
- +
6 V - +
6 V - +
6 V - +
6 V
- +
1 2 V
- +
1 2 V
+
-
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