Recommended Weight Distribution System, Solenoid and Power Inverter for Auxiliary Battery

Published 08/23/2018

Products Featured in This Question

Reese Steadi-Flex Weight Distribution System w/ Sway Control - Trunnion - 12K GTW, 1.2K TW

(238)

$805.86

10 Gauge Wire - Blue Primary - Per Foot

(103)

$1.83

2-5/16" Hitch Ball - 1-1/4" Diameter x 2-3/4" Long Shank - Chrome - 12,000 lbs

(2617)

$21.43

40 Amp In-Line Circuit Breaker - Perpendicular Mount Bracket

(97)

$9.86

2" Hitch Ball - 1-1/4" Diameter x 2-5/8" Long Shank - Chrome - 10,000

(3858)

$18.15

Reese Steadi-Flex Weight Distribution System w/ Sway Control - Trunnion - 10K GTW, 1K TW

(238)

$771.06

Question:

Ok thanks, but I have a couple follow ups, please, before I order On the isolator, I don't see a reason to connect anything to my ignition 12 volt, as the video indicates. My 2018 Ford already does not provide power through the trailer harness when the ignition is off. only the running lights work when ignition is off (IF the truck light switch is on). What Im doing really has nothing to do with the trailer, just another battery in the back of the truck to run dewalt chargers and the lights in the topper, maybe a fan. And, does the amp rating affect what can be done if I add a 110 v inverter onto the aux battery? why are other isolators rated at 200 amps, what would make someone need a 200 amp rating? Thanks for your help, I will get the Reese system as soon as I figure out the rest of the order.

asked by: Philip G

Expert Reply:

For your auxiliary battery in your Ford truck, I recommend using the Battery Isolation Solenoid # PK5231201. This will make sure your auxiliary battery does not drain your vehicle starter battery to ensure you will always be able to start your vehicle even if your trailer battery and auxiliary truck battery are drained. This will allow you to maintenance charge your auxiliary battery from your alternator when the vehicle ignition is turned on, but not when it is turned off. You won't have 80 amps of power going from one battery to the other.

For your weight distribution system, you would need to upgrade your entire system to the Reese Steadi-Flex Weight Distribution System w/ Sway Control # RP66560 which is rated for total tongue weights (loaded trailer tongue weight plus cargo weight behind rear axle) between 600 and 1200 lbs. This will have a different head and will require a hitch ball with a different diameter shank, so you will want the # A-90 for a 2 inch ball or # 19286 for a 2-5/16 inch hitch ball.

expert reply by: Jason S

Philip G.

8/23/2018

Jason S.

8/23/2018

The Battery Isolation Solenoid # TR118665 uses the ignition 12V pin to allow the power to travel from the battery through the solenoid. Without that connection, the solenoid will not allow the power draw. If you were to connect to your factory wiring after the ignition is tied into that 7-way power, then you won't need a separate solenoid as you mentioned. The 200 amp alternator supplies power to many functions of your vehicle other than just that 12V power at your 7-way, so that amperage is controlled when the power is flowing out so your components don't get a power surge. That is why you have fuses if something were to go bad and surge so your whole electronic system doesn't go down. For your application with a battery in the back of your vehicle you will want to simply run a 40 amp circuit breaker # 9510 between the 12V power of your trailer wire and your auxiliary battery positive terminal using # 10-1-1 sold by the foot. You can also use that same wire to run the negative terminal to a ground on your truck. This will provide a maintenance charge on the auxiliary battery as long as it isn't totally depleted. If it is depleted you will need to connect a traditional battery charger to get enough power base for this to charge. You can then run a power inverter like # WC3720 off that auxiliary battery with no problem for your DeWalt battery packs to charge and run a fan and lights. You will just want to make sure you have a deep cycle battery so it will last longer when the vehicle isn't running.