La Marche LTI2 PRO, Installation And Operation Manual

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13
Appendix B: Power Cabling Guide
Use the following formulas and table to determine proper wire size for minimal voltage drop. At distances
exceeding 10 feet, the DC wire size should be chosen to keep the voltage difference between the inverter ’s DC
input terminals and the battery at less than 1/2 volt when the inverter is fully loaded.
Table of Conventions:
CMA
= Cross-section of wire in circular MIL area
A
= Ultimate drain in amperes
LF
= Conductor loop feet
MaxAmp
= Maximum allowable amperes for given voltage drop
AVD
= Allowable voltage drop
K
= 11.1 for commercial (TW) copper wire
= 17.4 for aluminum
Calculating Wire Size Requirements:
AVD
K LF A
CMA
 
=
Calculating Current Carrying Capacity of Wire:
K LF
AVD CMA
MaxAmp


=
Size
(AWG)
Area
CIR.MILS
Size
(MCM)
Area
CIR.MILS
18 1620 250 250000
16 2580 300 300000
14 4110 350 350000
12 6530 400 400000
10 10380 500 500000
8 16510 600 600000
6 26240 700 700000
4 41740 750 750000
3 52620 800 800000
2 66360 900 900000
1 83690 1000 1000000
0 105600 1250 1250000
00 133100 1500 1500000
000 167800 1750 1750000
0000 211600 2000 2000000
Table 5 - Wire Size/Area Table