Wiring question

[OutbacKamper]

I still have all the hook-ups in my truck that were installed by 4Wheel Campers in 2004. The 4 eye bolts are now going to be used as tiedowns for my new (to me) Northern Lite camper (weight = 350KG, about 770lb) . My question is about the wiring:
I tried to get professional help for this but everyone is so busy that it would be almost the end of August before it would get done. So I am trying to do the job myself. I am going to reuse the electrical plug installed in the truck bed (I had to try several marine stores before I found one that can order me a new Marinco male plug). How do I wire the battery to the plug? I managed to succesfully hook a new battery up to the camper to run the fridge and lights, etc, but am not sure about how the wiring needs to be run from the truck charging system to the new camper battery (the battery is in the bed of the truck, as there is no room for one in the camper). I seem to remember that there was some type of battery isolator in the camper near the battery. If anyone can show me a picture of their stock battery, isolator and wiring, I would be very greatful.

My goal is to take my daughter camping in the new camper next weekend, so I am feeling a bit rushed, trying to sort this out.

Thanks
Mark

 

[Sam]

Mark,

I am by no means an expert in this subject but I'll tell you what I did and have been using for some time with no trouble.

My truck has a factory tow package wich includes the 7 way trailer wiring harness. One pin on the 7 way plug is 12v power for charging the battery on tow behind trailers. I simply spliced into this wire and ran it to a Marinco plug (www.westmarine.com) in my bed. I have read about the various isolators but don't really understand what they do or if you need one (I don't have one). The circuit I spliced into is fused 40 amp in the vehicles factory electrical system, I remove this fuse when I camp so that I don't drain the truck battery but I plan on installing a switch in the camper that allows me to dissconnect power from the truck.

Like you I was in a rush to use my camper so I came up with this charging system as sort of a temporary thing, that was about a year ago and about 7,000 miles so I guess it works and I have no plans to change the set up at this point.

Sam

 

[winter200]

What i would do is install the the 7 way plug from any parts store. Tap into the ground wire and the 12 constant power wire (as mentioned they are typically fused at around 40 amp). You should use an isolator so you don't wear down your battery in the truck. It is simply an oversized relay. You should be able to buy one from any parts store camping store. The isolator (relay) basically will just connect the camper battery with the truck battery when it gets a low amperage 12v signal from your ignition system. There is typically ign 12 volt power available @ the fuse panel or in the newer gm systems you can easily get it from under the dash at the midbec. There should be a wiring diagram on the isolator. If you are under a rush you probably don't need to worry about the isolator right away just remeber that the truck battery will be dead when the camper battery is dead. You just need to connect the 12v constant from the 7 way to the positive for the camper and the ground to the ground on the camper. Wouldn't hurt to put an inline fuse in the positive to protect the truck system. If you want you can just pull the 7way off the truck when you get to where you are going.

 

[benburnett]

wiring

Unless they have changed it, the Marinco plug should be #1 is the black, ground wire, #2 is the White, power wire and #3 is the running lights if you have them on the camper.

The old isolator was simple to install under the hood. Wire from your positive battery post to the large post on one side of the isolator. Wire from the other large post to the positive of the camper battery (IE: #2 on the plug.)

Wire from one of the small posts on the isolator to a hot wire in the truck when your key is on. We usually used a wiper wire for this. The other small post is for a ground wire to your truck body.

The ground on the plug can be connected to the frame of the truck.

If you would like a better explanation, feel free to call anytime.

800-446-1003

 

[jimjxsn]

Here is a diagram for wiring a battery isolator solenoid switch. Good Luck!

 

[Pete D]

I'm not familiar with the way the truck campers connect to the truck's battery but I am familiar some of the various schemes used for small travel trailers.

Because I like things to be more or less standard, and to fit various connections, I would tend to want the TC wiring to connect to a standard RV trailer connector so I could use it for more than one thing -- YMMV! I would use my existing 7-way Bargman-Pollack connector, but not use the brake wire, obviously.

What I have done on my trucks in the past is to put a 30Amp auto-reset circuit breaker http://aopecrelay.manufacturer.globalsources.com/si/6008816904281/pdtl/Circuit-breaker/1001852667/Auto-Reset-Circuit-Breaker.htm at the truck battery to protect the charging wire to the TC battery (I don't like a fuse because I won't know it's blown until the battery is dead... If it's triggered by more than a momentary short of some kind, I will either hear the clicking or the ARCB will burn up; they don't cost much). Get 'em at auto parts, Wally, etc.

BTW, Home Despot carries Marinco stuf in the electrical dept.

From my readings on various RV groups, the isolation relay is the best way to go, but DON'T use a starter relay because they don't hold up well in an always-on when ignition is on application.

The two conditions under which an isolation relay will really shine are if you have a reefer with a 12VDC mode or if you are running your furnace fan for a long time.



Also, don't use the diode-based isolation systems because they can put a 0.5VDC drop in the charging system and that will result in a significant drop in the percentage charge on the TC battery.

Also, when I wire the trailer connector, I extend the white (negative return/ground) wire not only to the truck frame but also all the way back to the truck battery's negative terminal, rather than relying on frame grounding and connections that may come loose or get corroded. Many (all?) modern trucks no longer rely on frame ground for any wiring except the starting system.

 

[Stan@FourWheel]

Hello OutbacKamper

I'm not sure how the wiring is for the new camper you have, but here are some sample pictures of different camper battery set ups I have seen in the past on the FWC's. Remember, the pics attached might be more confusing than helpful (laughs). There is about 5 different pics below and each is of a different wiring. I'm hoping you can take what you can to make sense of it all and wire your new camper sucessfully.

I thought most other camper brands use a 6 or 7 pins connector, but I could be wrong ?

I would hate to steer you the wrong direction and have you short something out.

Maybe best to get some in-line fuses just to be on the safe side.

If you e-mail me at ... stan@fourwh.com I can e-mail you a copy of the current wiring install instruction we use now. I CAN'T guaranty that will work for your camper because I'm not sure how it is wired, but it might give you a better idea on how it is all done.

Here are some sample pics that might better show you as well.

Here is a link to the Marinco plug instruction ...

http://www.fourwheelcampers.com/MARINCOCAMPERPLUG.pdf


Talk to you soon ...



,

 

[chnlisle]

I've wired all my campers pretty much like the diagrams but I've never included a thermal breaker. What is the purpose of it?

 

[benburnett]

thermal breaker

We used to put the thermal breakers in as a safety device in case someone tried to jump start off the battery and hooked it up wrong. It would trip the thermal breaker and as it cooled down it would close again, protecting the wiring in the camper.

We use an in line 30 amp fuse today for the same reason.

 

[OutbacKamper]

Thanks everyone for your detailed responses!
I am trying to locate a local supplier who has a Sure Power "smart solenoid" battery seperator (which is what was in the 4Wheel camper). Lots of people can order me one, but I am looking for something in stock - still hoping to go camping this weekend. I may have to live without charging the battery on this first trip.
Once again thanks and I will let you know how I make out once I have the correct parts.

Pete D said: "BTW, Home Despot carries Marinco stuf in the electrical dept"....now you tell me! I was just there and never thought to look for Marinco parts

Cheers
Mark

 

[jimjxsn]

Mark, I once picked up a solenoid battery seperator at a Checker auto parts store.

Alternatively you could temporarily install a manual switch in its place until you can get the battery seperator. That way you could at least charge the camper. Just don't forget to turn the switch off when you stop to camp.

 

[chnlisle]

Ben
That was my thought as well I have a 30A inline fuse and figured it would do the trick.

 

[Pete D]

The thermal breaker is also the auto-reset circuit breaker if the auto-reset model is purchased (nothing special about the thermal part as that's how many circuit breakers operate). My guess is that the in-line fuse and the breaker are redundant protection (unless one considers the breaker to be protecting the fuse if the breaker is faster than the fuse...).

Come to think of it, the fuse is also thermal Breakers, at $5-6, are less expensive in the long run than ATC/ATO fuses; personally, I don't like the in-line glass fuse holders because they tend to have corrosion problems, esp around batteries...

http://www.crowbarelectricalparts.com/Fuses_and_Fuseholders.htm

 

[Pete D]

The thermal breaker is also the auto-reset circuit breaker if the auto-reset model is purchased (nothing special about the thermal part as that's how many circuit breakers operate). My guess is that the in-line fuse and the breaker are redundant protection (unless one considers the breaker to be protecting the fuse if the breaker is faster than the fuse...).

Come to think of it, the fuse is also thermal

Breakers are less expensive in the long run than ATC fuses if you buy the fuses in onesy-twosy; personally, I don't like the in-line glass fuse holders because they tend to have corrosion problems, esp around batteries and prefer the covered ATC holders.

http://www.crowbarelectricalparts.com/Fuses_and_Fuseholders.htm

 

[chnlisle]

Pete,
When it comes to airplane systems and my electrical system I say you cant have too much redundancy. I've got everything fused all over the place just in case I did something wrong. Which for me is a daly occurance.

 

[Pete D]

I hear you about redundancy.

Actually, what I have done on my wiring systems is an auto-reset circuit breaker at the truck battery and another at the house battery, with no fuses in the system -- I don't want to find the fuse was blown by discovering a dead battery when I expected a live one. I got the idea from the trailer brake control specifying an ARCB for the brake wire (apparently so one doesn't have to climb out on the hood to change a fuse whilst rocketing down a mountain pass...)

 

[chnlisle]

Great idea. Where is it available?

 

[Pete D]

Auto-reset circuit breakers (ARCB - aka Type 1 thermal recycling) are available all over the place, like auto parts stores, Ace Hdwr and even WalMart. I believe they come in sizes from 6 to 50Amps and a variety of different ways to fasten them down. Some ARCBs are marked as to which terminal is the battery or the load, so pay attention to that.

Hmm, I wish I'd known there are "boots" available for them; I tie-wrapped some split cable loom over mine in case someone clumsy dropped a tool on them...

I made up a short wire between a copper lug on one screw of my battery terminal (my Ranger is Mazda-based, so it uses the steel battery clamps, not lead ones) and put crimp ring terminals on the ARCB.

BTW, if you are using crimp terminals, do NOT tin/solder the wire ends before crimping -- The solder may 'cold creep' over time and pressure and the connection will loosen.

 

[chnlisle]

Thanks Pete I'll be working on that today.

 

[craig333]

I use nothing but heat shrink connectors now. Some even come with solder inside. A little pricey but it makes a good strong connection.