GE Industrial Solutions Galaxy Power Systems - Manual (Page 30)

Installation Guide for Galaxy Power Systems
2 - 6 Safety Issue 12 August 2012
Precautions, continued
Note: Provide cable run lengths as least as long as the minimum length
indicated in Table 2-A to assure that the short circuit currents are less
than the interrupt current rating of the fuse or circuit breaker chosen.
1. Find the interrupt current rating of the chosen fuse or circuit
breaker from Table 2-B.
2. See Table 2-A for the minimum length (L) for the engineered cable
size to be run at the interrupt rating found in Step 1.
A minimum cable length for a given cable size and protector type must
be used to ensure proper short circuit protection in the case of a bolted
fault.
Table 2-A: Cable Run Lengths
Cable Size
Minimum Length “L” Required to Limit the Current to an
Interrupt Rating of:
100KA 25KA 10KA
10 GA
(6mm
2
)
-- -- 5 feet
8 GA
(10 mm
2
)
-- -- 8 feet
6 GA
(16 mm
2
)
-- 5 feet 12 feet
4 GA
(25 mm
2
)
-- 8 feet 19 feet
2 GA
(35 mm
2
)
3 feet 12 feet 30 feet
1/0 GA
(50 mm
2
)
5 feet 19 feet --
2/0 GA
(70 mm
2
)
6 feet 24 feet --
4/0 GA
(120 mm
2
)
10 feet 38 feet --
(2) 4/0 GA
((2) 120 mm
2
)
19 feet 76 feet --
(3) 4/0 GA
((3) 120 mm
2
)
29 feet 113 feet --
350 MCM 17 feet 63 feet --
(2) 350 MCM 32 feet 125 feet --
(3) 350 MCM 47 feet 188 feet --