Ametek Sorensen Asterion DC Series, Operation Manual

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Asterion DC Series Installation
M330460-01 Rev D 2-29
the performance specifications of this power source. Also, consider how the wiring
codes apply to bundles of wire within a cable arrangement.
In high performance applications requiring high inrush/ transient currents, additional
consideration is required. The cable wire gauge must accommodate peak currents
developed at peak voltages, which might be up to five times the RMS current values.
An underrated wire gauge adds losses, which alter the inrush characteristics of the
application and thus the expected performance.
Table 2-8 presents wire resistance and resulting cable voltage drop at maximum
rated current, with the wire at 20°C. Copper wire has a temperature coeffi
cient of α =
0.00393Ω/°C at t1 = 20°C, so that at an elevated temperature, t2, the resistance
would be R2 = R1 (1 + α (t2 - t1)).
The output power cables must be large enough to prevent the line voltage drop (total
of both output wires) between the power source and the load from exceeding the
remote sense capability as presented in the specification section. Calculate the
voltage drop using the following formula:
Voltage Drop = 2 × distance-in-feet × cable-resistance-per-foot × current
Table 2-8. Wire Resistance and Voltage Drop, 20°C
2.13
Load Considerations
This section provides guidelines for incorporating protective diode networks at the output
of the power supply to prevent damage while driving inductive loads or loads having
stored energy that could be circulated back to the power supply.
Size,
AWG
A(RMS),
(90°C wire)
Ohms/100 Ft,
(One Way)
Voltage Drop/100 Ft,
(Column 2 x Column 3)
18 14 0.639 8.95
16 18 0.402 7.24
14 25 0.253 6.33
12 30 0.159 4.77
10 40 0.100 4.00
8 55 0.063 3.47
6 75 0.040 3.00
4 95 0.025 2.38
3 115 0.020 2.30
2 130 0.016 2.08
1 145 0.012 1.74
0 170 0.0098 1.67
00 195 0.0078 1.52
000 225 0.0062 1.40
0000 260 0.0049 1.27