Technical Document MI-0307A Produced by the Electrical Rebuilder’s Association www.electricalrebuilders.org Total System Length (length of positive feed + length of negative return) in inches WIRE SIZING CHART 24″ | 48″ | 72″ | 96″ | 120″ | 144″ | 168″ | 192″ | 240″ | 288″ | 336″ | 400″ | 500″ | 600″ 10 | 16ga|16ga|16ga|14ga| 14ga | 14ga | 12ga | 12ga | 10ga | 10ga | 10ga | 8ga | 8ga | 6ga 15 |16ga|16ga/|14ga|14ga| 14ga | 12ga} 10ga | 10ga | 8ga | 8ga | 8ga | 6ga | 6ga | 6ga 20 | 16ga| 14ga|14ga|1i2ga| 12ga | 10ga | 10ga | 8ga | 8ga | 8ga | 6ga | 6ga | 4ga | 4ga 25 |14ga|14ga|12ga|10ga| 10ga | 10ga| 8ga | 8ga | 6ga | 6ga | 6ga | 4ga | 4ga | 2ga 30 |14ga/14ga/12ga|10ga| 10ga| 8ga | 8ga | 8ga | 6ga | 6ga | 4ga | 4ga | 2ga | 2ga 40 |14ga|12ga|10ga| 8ga| 8ga | 8ga | 6ga | 6ga | 4ga | 4ga | 4ga | 2ga | 2ga | i1ga 50 |12ga/12ga/10ga| 8ga | 6ga | 6ga | 6ga | 4ga | 4ga | 4ga | 2ga | 2ga | iga | 1/0 LJ 60 |12ga|10ga| 8ga | 8ga | 6ga | 6ga | 4ga | 4ga | 4ga | 2ga | 2ga | iga | 1/0 | 1/0 o 70 |12ga|10ga| 8ga | 6ga | 6ga | 4ga | 4ga | 4ga | 2ga | 2ga | 2ga | iga | 1/0 | 2/0 w~ 80 |12ga| 8ga | 8ga | 6ga | 4ga | 4ga | 4ga | 2ga | 2ga | 2ga | iga | 1/0 | 2/0 | 2/0 uu 90 |12ga} 8ga | 6ga | 6ga | 4ga | 4ga | 2ga | 2ga | 2ga | iga | 1/0 | 1/0 | 2/0 | 3/0 => 100|10ga| 8ga | 6ga | 4ga |} 4ga | 4ga | 2ga | 2ga | iga | 1ga | 1/0 | 2/0 | 3/0 << 120|10ga| 8ga | 6ga | 4ga |} 4ga | 2ga | 2ga | 2ga | iga | 1/0 | 2/0 | 3/0 => 140|10ga| 6ga | 4ga | 4ga |} 2ga | 2ga | 2ga | iga | 1/0 || 2/0 | 2/0 | 3/0 2-2/0 = 160| 8ga | 6ga | 4ga | 2ga |} 2ga | 2ga | 1ga | 1/0 | 2/0 | 2/0 | 3/0 2-2/0| 2-3/0 CJ |180| 8ga | 6ga | 49a | 2ga | 2ga | 1ga | 1/0 | 1/0 | 2/0 | 3/0 2-2/0 | 2-2/0 | 2-3/0 2D 200| 8ga | 4ga | 4ga | 2ga | iga | iga | 1/0 | 2/0 | 3/0 | 3/0 2-2/0 | 2-3/0 250| 6ga | 4ga | 2ga | iga | 1/0 | 1/0 | 2/0 | 3/0 | 3/0 2-2/0 | 2-3/0 300) 6ga | 4ga | 2ga| iga| 1/0 | 2/0 | 3/0 | 3/0 2-2/0| 2-3/0 350| 6ga | 2ga | 1ga | 1/0 | 2/0 | 3/0 | 3/0 2-2/0 | 2-3/0) 2-3/0 400| 4ga | 2ga | iga | 2/0} 3/0 | 3/0 2-2/0 | 2-3/0 | 2-3/0 450| 4ga | 2ga | 1/0 | 2/0 | 3/0 2-2/0| 2-3/0 500| 4ga | 1ga | 1/0 | 3/0 2-2/0 | 2-3/0| 2-3/0 600| 4ga | 1ga | 2/0 | 3/0 2-2/0 | 2-3/0| 2-3/0 700| 2ga | 1/0 | 3/0 2-2/0 | 2-3/0| 2-3/0 This table was calculated for a 12-volt system, assuming a .36 voltage drop for starting and a .44 voltage drop for charging, a a maximum operating temperature of 150°F. A larger size wire can be used to decrease thevoltage drop or to operate at a higher temperature. For 6-volt use, multiply amperage by two. For 24-volt use, divide amperage by two. Created by Wes Grueninger for the Electrical Rebuilder’s Association- © 2007, Electrical Rebuilder’s Association — All rights reserved No portion of this guide may be reproduced in any way, or stored in any electronic retrieval system without the prior written consent of the Electrical Rebuilder’s Association.