What is the Maximum Amperage Draw of Trailer Brake Magnets on a Tandem Trailer with Four Brake Drums

Updated 05/05/2010 | Published 05/02/2010

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Deka Jacketed 2 Wire, 10 Gauge, Brake Wire - per Foot

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Question:

What is the full load amperage that four drum magnets draw? I have four magnets on four drums. I dont know the drum size just now, but they are on a 25 foot goose-neck horse trailer. Right now they are fed with 2 conductor 14 gauge wire from the factory. Is this right , or should I change it out to 10 gauge? Thanks

asked by: Ed S

Expert Reply:

Maximum amperage draw for 4 Brakes that are 10 or 12 inch diameter is 15.0 to 16.3 amps at 12 to 13 volts.

The 14 gauge wire may be sufficient but for maximum braking effectiveness at full load capacity. I would opt to run 10 gauge wire. Larger wire will only help the effectiveness of the trailer brake system and 10 gauge is what we use when installing trailer brakes even on single brake axles with 7 inch brake assemblies.

We offer Jacketed 2 Wire, 10 Gauge, Brake Wire, item # 10-2-1, by the foot, for replacing the brake wiring on your trailer. When ordering just enter the number of feet needed in the quantity box.

I have linked a trailer brake installation and wiring video for your to review.

expert reply by: Robert G