What Circuit Breakers Are Needed When Adding a Trailer Brake Controller and Charge Line?
Updated 02/03/2026 | Published 07/16/2024
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Question:
i have a 1994 chevrolet k1500 blazer, and will be towing a 2024 coleman rubicon 1400bh. I am currently ready to connect the wire from my brake controller to my battery, and also the wire from my 7pin connector to my battery. The wire from 7pin to battery is likely 10awg, its thick. It was installed from the factory and does not seem to mention the gauge anywhere on the insulation. The wire from the brake controller to the battery is 12awg. I am wondering what size circuit breakers I should use for these 2 wires. I currently plan to only ever tow this 1 camper with 1 axle. But for some reason if I needed to tow a 2 axle, Id like to be ready. I dont want to use a breaker that is so big, the wire will melt before the breaker does anything, or one that is so small that it breaks constantly. Any help would be appreciated!
asked by: Justin
Expert Reply:
We typically install a 40-Amp Breaker # PK54540 for the charge line and either a 20-Amp # PK54520 or 30-Amp # PK54530 breaker for the brake controller. This will depend on the requirements of your brake controller so you will want to check the instructions for your controller. The 40-amp breaker can safely be used on 10 gauge wire as it is what we include in our 7-Way Kit # ETBC7.
Product Page this Question was Asked From
Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket
- Accessories and Parts
- Wiring
- Circuit Breaker
- 40 Amp
- Pollak
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Samuel C.
2/3/2026
Hey, how did things go with the 40-amp and 20- or 30-amp breakers on your Blazer’s wiring setup? Your results could really help others figuring out the right match for their brake controller and charge line.