Recommended Vehicle To Trailer DC to DC Charger for Multiple Trailer Batteries

Updated 01/23/2018 | Published 01/22/2018

Products Featured in This Question

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

(87)

$620.00

60-Amp MIDI Fuse Kit for Redarc In-Vehicle 40-Amp BCDC Battery Charger

(21)

$90.00

60-Amp Relay Kit for Redarc In-Vehicle BCDC Battery Charger

(5)

$125.00

Dutton-Lainson Electrical Quick Connect for TW4000 Electric Winches

(9)

$22.21

Question:

I am wanting to charge my trailer battery while towing. I currently have the Hopkins H20046 7 pin cable, Hopkins HM48470 7 pin connector, and CTEK40186. From my research it seems the Auxiliary Power wires will not be sufficient gauge wise to charge my batteries. My question is should I forego the auxiliary wire and run a separate 8 gauge wire from the starter battery to the CTEK 250 located on the trailer? Utilizing these connectors Dutton DL24086. Mounting the connectors next to the HM48470 on the rear bumper.

asked by: Wayne

Expert Reply:

Your auxiliary power wire gauge at your 7-way along with the discontinued CTEK40186 will be sufficient to charge your trailer batteries. The CTEK D250S will amplify the signal from your auxiliary power to boost it to 20 amps versus the 2-3 amps of a system without the CTEK unit. Changing your gauge of wire to 8 and adding the # DL24086 connections will help slightly but if you are wanting to charge multiple batteries well and more quickly/efficiently, you really will want the discontinued CTEK SmartPass Energy Management Unit for CTEK D250S. This will handle charging larger service batteries in parallel. This charges the service batteries more efficiently while protecting them from overcharging or overheating.

If you didn't already have the D250S, or if you don't have the smartpass, my recommendation is the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp # 331-BCDC1240D which will work very well for you using Fuse kit # 331-FK60. If you have a smart alternator then you will also want # 331-RK1260 which will allow the charger to recognize the smart alternator without a direct connection to the ignition source.

expert reply by: Jason S