Communication Server Large System Installation and Commissioning

Page 120 of 456 Installing DC power
NN43021-310 Standard 02.01 December 2007
A maximum loop drop of 2 V is allowed between the pedestal, or junction
box, and the external power equipment. See Table 5 for allowable wire sizes.
See Communication Server 1000M and Meridian 1: Large System Planning
and Engineering (NN43021-220) for detailed information on calculating wire
size.
Table 5
Wire gauge requirements with two 30 A feeds (five wires)
Length #8 AWG #6 AWG Single #4 AWG Double #4 AWG
0 to 3m (10ft) Ye s Ye s Ye s Ye s
3 to 6m (20ft) Ye s Ye s Ye s Ye s
6 to 9m (30ft) Ye s Ye s Ye s Ye s
9 to 12 m (40 ft) Ye s Ye s Ye s Ye s
12 to 15 m (50 ft) Ye s Ye s Ye s Ye s
15 to 18 m (60 ft) No Ye s Ye s Ye s
18 to 21 m (70 ft) No Ye s Ye s Ye s
21 to 24 m (80 ft) No Ye s Ye s Ye s
24 to 27 m (90 ft) No No Ye s Ye s
27 t o 30 m
(100 ft)
No No Ye s Ye s
30 to 60 m
(200 ft)
No No No Ye s
over 60 m (200 ft) No No No No
Note 1: Two 30 A feeds are typically adequate for a column with four modules (five wires
total—two 30 A feed pairs plus logic return).
Note 2: If dual conduit is used, the wires must be run in battery/battery return pairs, with one
pair in one conduit and the other pair, plus logic return, in the other conduit.
Legend:
Yes = Wire size is adequate for the distance.
No = Wire size has too high a voltage drop and is inadequate for the distance.