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Topic: Source for towed charge line current (Read 511 times) previous topic - next topic

Source for towed charge line current

I am adding a charge line for my towed.  Does it matter whether I tap into the house batteries or the coach batteries to supply the electrons?  I plan to tap in at the isolator in the engine compartment.

Thanks,

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Source for towed charge line current

Reply #1 –
Rich, it should already be wired in your plug, it's the top right in the 1 o'clock position when the notch in the housing is at the bottom.
All you should need to do is wire the towd.
David
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

Life is made to enjoy, the Foretravel helps!

Re: Source for towed charge line current

Reply #2 –
Rich it is smart to have a fuse at both ends of the wire.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Source for towed charge line current

Reply #3 –
Quote from: oldguy –
Rich it is smart to have a fuse at both ends of the wire.
Absolutely, it is. Use a current limiting device on the coach end, as well as the towed end, sized for the lightest conductor in the circuit. Self resetting breakers, like FT uses on our coaches, work very well for this.

Greg
Greg & Cathy
2000 U320 4010 DGFE Build #5650
Had: 1999 Tradewinds 7370

Re: Source for towed charge line current

Reply #4 –
Quote from: oldguy –
Rich it is smart to have a fuse at both ends of the wire.
The factory six pin plug does not have a battery charge wire or backup light. Your new seven pin can be wired with both but you will need to add a taillight converter before the plug. Will use same light circuit for turn and brake thru the controller. I used the large spare wire and had a 30amp self resetting circuit breaker on the coach power not house. It might be nice on the house come to think of it? 15 amp on reverse circuit. Some of the nicer socket setups will have fuses at the socket. I also added the backup light circuit because I seem to regularly back up too much. Led cube lights on the back of the trailer are real nice and this also gives a trigger if you have a camera on the back of trailer. I need. All the help I can get. Every time I move my coach it includes 200 feet of backing up with a dogleg in the middle to block view from the street.
Amazon.com: Hopkins 48845 12 Tail Light Converter: Automotive
Scott
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Source for towed charge line current

Reply #5 –
The round center pin wiring diagram for my factory 2001 coach round 6 pin connector was empty, so, I ran a fused, 12v wire to that pin from my isolator.  The towed gets it's voltage for an add-on trickle charger through that pin connector.  Option I guess is to connect a tow brake signal to that pin, and then it would require a completely different wiring connector, but I use a RVI Brake (brake buddy) which does not need an external brake signal, and that factory 6 pin connector with the center pin charge voltage has kept the towed battery fully charged during tow for the past 2 years and 16,000 miles on 2 different toads.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Source for towed charge line current

Reply #6 –
Thanks for the inputs.

I have already taken the coach 7-pin connector apart for wiring.  There is no 12V charge wire in the existing 7-pin OEM connector on the coach. 

Yes, I have already added a self-resetting CB to the towed end of the line and have one for the coach end. 

I don't plan to/can't backup with the jeep attached so don't need backup lights. 

Just trying to figure out if it makes any difference if I pull my 12V for charging from the coach or chassis side of the isolator.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Source for towed charge line current

Reply #7 –
Quote from: Rich Bowman –
Just trying to figure out if it makes any difference if I pull my 12V for charging from the coach or chassis side of the isolator.

Rich,

Electric wise there really isn't any difference, but I use the chassis side because the function we are doing is related to the chassis side rather than the coach side of the system.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Source for towed charge line current

Reply #8 –
Thanks, that was the way I was leaning.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Source for towed charge line current

Reply #9 –
Rich, good plan to hve CB or fuse close to the battery (or source)  at each end.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Source for towed charge line current

Reply #10 –
I ran a wire with a resettable circuit breaker at each end via the unused center pin. Worked great on my Acura MDX.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Source for towed charge line current

Reply #11 –
I have a preference for using a fuse rather than a resettable breaker for the toad battery charge wire (yes, at both coach and toad battery connection points.

The reason is particularly important for an issue at toad battery end.  A short (the wire from toad battery wearing through and contacting any metal/ground) with a resettable breaker can repeatedly make/break/make and potentially quickly deplete the toad battery.  Yes, a fuse would blow, but would not quickly and deeply discharge the toad battery.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Source for towed charge line current

Reply #12 –
I came off front fuse panel, keyed source from engine batteries, with auto breaker. Used one of the extra heavy wires in the factory harness to rear.

I also converted to 7 round, and use the correct post for charge wire. It charges my Jeep, and my race car trailer, or any other thing I charge that has correct charge wired into plug.

#4 on plug:

https://www.etrailer.com/question-30179.html

Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348