Instruction manual

POWER AND GROUNDING
Table Q provides the requirements for input DC power.
TABLE Q. -48 Volt DC Input Power Requirements
Parameter Requirements
Static Voltage -48 V DC nominal, -42.5 V DC minimum, -52.5 V DC maximum
(measured at input to system cabinet)
Dynamic Voltage Transient change in voltage (+/- 5% of steady state voltage)
Allowed transient duration (up to 200 milliseconds)
AC Ripple Voltage Maximum wideband AC ripple (450 mvpp in the 3 kHZ-to-20 MHZ
band)
Low Voltage Disconnect Automatic disconnect occurs when input voltage becomes less than
-42.5 V DC (control provided with battery plant).
Overvoltage Protection Input voltage shall not exceed -52.5 V DC.
Voltage Drop Maximum drop must not exceed 0.5 V DC one-way on feeder cable
between the power board and the system cabinet.
Feeders must be UL approved and CSA certified.
Feeder gauge must be no smaller than 6 AWG and no larger than
1/0 gauge.
Recommended -48 V DC feeder cable— Royal Electric #4905 or
equivalent
1-AWG is required for distances up to 50 feet.
Cable resistance must be equal to or less than 0.1290 ohms per
1000 feet.
Current Draw The battery plant rectifiers must be capable of providing current for
the system, including current required for system holdover and for
charging the batteries. In addition, this may include DC current
required for an inverter that provides AC power to peripheral equip-
ment, if it is installed, and for future growth.
Circuit Breaker A UL-listed and CSA-certified circuit breaker must be provided at the
battery plant power board for each system cabinet feeder.
The recommended circuit breakers are 75 ampere Airpax UPLI-1-
REC2-52-753 or Heinemann AM1-B2-A-75-2 .
123