EnerSys alpha CXPS-E3, Руководство пользователя

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35 9400016-J0 Rev E
CXPS-E3 User Guide
7. Wiring
This chapter provides cabling details and notes on cable sizing for DC applications with respect to the product.
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 voltmeter to verify the
absence of a voltage. Clearly mark the correct polarity of the battery leads before starting work
on DC connections.
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 exceed electrical code
requirements, mostly due to the voltage drop requirements, all applicable electrical codes 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 following
formula 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 (for example, NEC, CEC.) for guidelines. If required, increase the size of the cable to meet
the code.
Refer to Table F for cable size equivalents.
Table F — Cable size equivalents (AWG to Metric)
Cable size 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
WARNING!
The CXPS-E3 must be installed above a non-combustible surface.