Can 16 Gauge Wire be Used for Battery Isolator Solenoid

Updated 03/24/2022 | Published 03/23/2022

Products Featured in This Question

Starter Solenoid - SPST - 12 Volt - 100 Amp - Continuous Duty - Grounded

(14)

$35.41

10 Gauge Wire - Blue Primary - Per Foot

(108)

$1.65

Question:

Hi, I installed an auxiliary battery in my trailer, From my vehicle’s battery I ran a 8awg wire to the 7way plug with a 35AMP Automatic Reset Circuit Breaker and a battery isolator solenoid PK5231201 in between, the solenoid is powered by a 16awg +wire, is 16awg enough to run for hours? The problem is that this solenoid PK5231201 gets very hot 35°/40°C after 30/40min. Even without the 8awg battery wires connected Is this normal? What about when I travel for hours? I don’t want to burn my new vehicle. Should I do something different? Thank you

asked by: Joe

Expert Reply:

Yeah you definitely need to be running at least 10 Gauge Wire # 10-1-1 for the Battery Isolation Solenoid # PK5231201. The 16 gauge wire size is typically used for vehicle and trailer lights which don't draw nearly as much power, but for the 12V power that's charging your trailer battery you really need larger wire.

As long as you're using the larger wire and you have the isolator solenoid installed with a good ground any heat you see it build up isn't something to worry about. It'll probably run cooler once you have that 12V power running back to the 7-Way plug as well since it won't all be building up right there.

expert reply by: Jon G