EnerSys Alpha Cordex HP 3.0kW, Техническое руководство

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0100037-J0 Rev C 18
7. Wiring
This chapter provides cabling details and notes on cable sizing for DC applications with respect to the product.
7.1 Installation Notes
Refer to the Installation section for safety precautions and tools required.
7.1.1 Calculating Output Wire Size Requirements
Although DC power wiring and cabling in telecommunication applications tend to ex-
ceed electrical code requirements, mostly due to the voltage drop requirements, all
applicable electrical code(s) take precedence over the guidelines and procedures in the
present chapter, wherever applicable.
Wire size is calculated by first determining the appropriate maximum voltage drop requirement. Use the formula
below to calculate the circular mil area (CMA) wire size requirement. Determine the size and number of conductors
required to satisfy the CMA requirement.
CMA = (A x LF x K) / AVD
A = Ultimate drain in amps.
LF = Conductor loop feet.
K = 11.1 constant factor for commercial (TW type) copper wire.
AVD = Allowable voltage drop.
Check again that the ampacity rating of the cable meets the requirement for the installation application. Consult local
electrical codes (NEC, CEC, etc.) for guidelines. If required, increase the size of the cable to meet the code.
Refer to Table B for cable size equivalents.
Table B — Cable size equivalents (AWG to Metric)
Cable size
(see notes 1 and 2)
Circular mils Square millimeters Equivalent metric
cable
20 AWG 1020 0.519 1
18 AWG 1624 0.8232 1
16 AWG 2583 1.309 1.5
14 AWG 4107 2.081 2.5
12 AWG 6530 3.309 4
10 AWG 10380 5.261 6
8 AWG 16510 8.368 10
6 AWG 26250 13.30 16
4 AWG 41740 21.15 25
2 AWG 66370 33.63 35
0 AWG (or 1/0) 105600 53.48 50 or 70
00 AWG (or 2/0) 133100 67.42 70
WARNING!
Ensure that the power is switched off by switching off rectifiers and removing battery
line fuses, turn off battery breakers before attempting work on the wiring. Use a volt -
meter to verify the absence of a voltage. Clearly mark the correct polarity of the battery
leads before starting work on DC connections.