Step 4: selecting load wires, Load wiring, Insulation rating – Xantrex Technology XTR 850 Watt User Manual
Page 39: Current carrying capacity, Step 4: selecting load wires –9, Load wiring –9, Table 2-3, Current carrying capacity for load wiring –9
Step 4: Selecting Load Wires
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Step 4: Selecting Load Wires
This section provides recommendations for selecting minimum load wire
sizes.
Load Wiring
To select the wiring for connecting the load to the power supply, consider
the following factors:
•
Insulation rating of the wire.
•
Current carrying capacity of the wire.
•
Maximum load wiring length for operation with remote sense lines.
•
Electrical noise and impedance effects of the load lines.
Insulation Rating
Use load wiring with a minimum insulation rating equivalent to the
maximum output voltage of the power supply.
Current Carrying Capacity
The load wiring must have a current carrying capacity greater than the
output rating of the power supply to ensure that the load wiring will not be
damaged if the load is shorted. Table 2-3 shows the maximum current
rating for various gauges of wire rated for 105 °C operation, based on a
maximum current density of 450 A/cm
2
.
Operating at the maximum current rating shown in Table 2-3 results in an
approximately 30 °C temperature rise for an appropriately-sized load wire
operating in free air. Where load wiring must operate in areas with
elevated ambient temperatures or bundles with other wiring, use larger
gauges or wiring rated for higher temperatures.
Table 2-3 Current Carrying Capacity for Load Wiring
Wire Size
(AWG)
Maximum Current
(Amps)
Wire Size
(AWG)
Maximum Current
(Amps)
20
2.5
6
61
18
4
4
97
16
6
2
155
14
10
1
192
12
16
1/0
247
10
21
2/0
303
8
36