IBM N7800, Hardware And Service Manual

Page: 163 / 182

Appendix A. Recommended power line sizes
This appendix discusses how to determine the power line lengths running from
your N7000 series system to the power source.
Recommended AC power line sizes
Longer AC power feeds need to be properly designed to preserve voltage levels to
the equipment. The wiring from the breaker panel to the power strip, which
supplies power to your N7000 series system and storage expansion units, can often
exceed 50 feet.
Note: Total AC wire length = breaker to wall or ceiling extension cable or
ceiling drop.
The following table lists the recommended conductor size for 2% voltage drop for
a particular distance in feet (taken from the
Radio Engineer's Handbook ).
Table 16. 110V, single phase recommended conductor sizes
110V, single-phase 20A circuit 30A circuit 40A circuit 50A circuit
25 feet 12 AWG 10 AWG 8 AWG 8 AWG
50 feet 8 AWG 6 AWG 6 AWG 4 AWG
75 feet 6 AWG 4 AWG 4 AWG 2 AWG
Table 17. 220V, single phase recommended conductor sizes
220V, single-phase 20A circuit 30A circuit 40A circuit 50A circuit
25 feet 14 AWG 12 AWG 12 AWG 10 AWG
50 feet 12 AWG 10 AWG 8 AWG 8 AWG
75 feet 10 AWG 8 AWG 6 AWG 6 AWG
The following table list the approximate equivalent wire gauge (American Wire
Gauge (AWG) to Harmonized Cordage).
Table 18. American Wire Gage to Harmonized Cordage equivalents
AWG 8 10 12
Harmonized, mm-mm
1
4.0 2.5 1.5
1
mm-mm = millimeter squared
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