How to Charge a Trailer Battery for Use with a Bulldog Jack

Updated 04/17/2018 | Published 04/14/2018

Products Featured in This Question

Bulldog Powered Drive Trailer Jack - Drop Leg - A-Frame - 22" Lift - 4,000 lbs - Black

(480)

$374.99

Snap-Top Battery Box with Strap for Group 24 Batteries - Vented

(274)

$23.14

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp

(87)

$620.00

CTEK MULTI US 7002 12-Volt Universal Battery Charger w/ Pulse Maintenance and Backup Power

(94)

$199.99

2.5-Watt Solar Battery Charger

(119)

$40.78

Question:

If I understand what I have read it is better to mount a battery on the trailer to run the jack rather than wire it through and to avoid overheating the 7 way plug. Would it then be reasonable and safe to keep that battery charged through the 7 way plug? Also, would it be safe to keep the battery in a box inside the cargo trailer instead of outside? Thanks,

asked by: Keith W

Expert Reply:

What you described is actually the best solution!

Connecting your battery to 12V Power wire from the 7-Way on your trailer is a great way to provide a maintenance charge on your battery to operate a Bulldog jack like part # BD500199. Mounting a battery inside a box like part # 329-HM300BKS inside your trailer will further help to keep your battery safe from the elements (although battery boxes do a pretty good job at that).

Please note that the 12V power from your vehicle will not necessarily charge your battery, it will just help to maintain it. You can either use a battery charger like part # CTEK56353 to recharge your battery when an AC outlet is present, or use a battery charger like part # 331-BCDC1240D along with a solar panel like part # PTW2997 to help charge your battery in addition to the 12V power maintenance from your your tow vehicle.

I have attached a picture showing how the second method would be installed for you to reference should you decide to go that route.