Wire Size Selection; Fire Hazard - HP 654 A Series Operating Manual

Figure 4-3. Analog Connector
Wire Size Selection
The minumiim wire size required to prevent wire overheating still may not be large enough to
maintain a small enough load-lead voltage drop for good electrical performance. See "Remote
Sensing" and "OVP Considerations" for more information on this topic. Table 4-2 gives the
wire resistance for various stranded sizes to help you determine load-lead drop.
Fire Hazard
To satisfy safety requirements, load wires must be heavy enough not to
overheat when carrying the maximum short-circuit current of the power supply.
Table 4-2. Stranded Copper Wire Ampere Capacity and Resistance
AWG
No.
Area
(mm*)
Ampacity
Resistance
(n/m)
II
AWG
No.
Area
(mm*)
Ampacity Resistance
(fl/m)
18
0.82 15.4
0.0210
8 8.37
75
0.0020
16
1.31 19.4
0.0131
6
13.3 100
0.<X)13
14 2.08
31.2
0.0082
4
21.1 135
0.0008
12 3.31 40.0
0.0052 2
33.2 180
0.0005
10 5.26
55.0 0.0033
1/0 53.0
245
0.0003
Notes:
1. AWG wire rating derived from MIL-W-5088B,
2
.
Ampacity of aluminum wire is apprloxiamtely 84% that of copper wire.
3. With bundled wires, use the following percentages of the rated ampacity:
2 conductors 94% 4 conductOTS 83%
3 conductors 89% 5 conductors 76%
4. Maximum temperatures: ambient = 50® C; conductor = 105® C.
4-4 User Connections and Considerations
Wire Selection