grounding 12v to trailer frame?

[Chuckles]

I have a 12 volt only system and I was wondering if I have to run a ground wire from the battery to the trailer frame? I am using a blue sea fuse panel connected to the positive and negative battery poles with 10ga wires. Should I run a separate wire from the fuse panel to the trailer frame as well? I was wondering because none of the switches or LED lights come with a ground wire or means of grounding.

Thanks.

Chuck

[eggsalad]

no, No, NO.

You want to keep the camper's 12V system totally isolated from your tow vehicle's 12V system.

[bdosborn]

no, No, NO.

You want to keep the camper's 12V system totally isolated from your tow vehicles 12V system.

Why is that? It's required by the NEC and RVIA to ground the battery to the frame...

Bruce

[eggsalad]

no, No, NO.

You want to keep the camper's 12V system totally isolated from your tow vehicles 12V system.

Why is that? It's required by the NEC and RVIA to ground the battery to the frame...

Bruce

Not that I disbelieve you, but what's the point? It's not like the trailer's chassis is a true ground anyhow... the tires isolate the chassis from true earth.

[bdosborn]

It's more of an issue with 120V than with 12V but here's one good reason:

Hot Skin Issue

On the 12V side, grounding the frame is more for electrical devices that might use the frame as a return path but there's a safety issue as well. Even though there aren't any known electrocution deaths in the US from voltages lower than 48V DC, it doesn't hurt to ground the frame. The idea is to have a fuse blow if a hot wire ever lands on the frame, rather than have the frame unknowingly energized and you complete a circuit with a wrench or through the trailer hitch.

Bruce

[GuitarPhotog]

And if you want to charge the battery from your tow vehicle, the two systems have to share a common ground.

<Chas>

[eggsalad]

It's more of an issue with 120V than with 12V but here's one good reason:

Hot Skin Issue

On the 12V side, grounding the frame is more for electrical devices that might use the frame as a return path but there's a safety issue as well. Even though there aren't any known electrocution deaths in the US from voltages lower than 48V DC, it doesn't hurt to ground the frame. The idea is to have a fuse blow if a hot wire ever lands on the frame, rather than have the frame unknowingly energized and you complete a circuit with a wrench or through the trailer hitch.

Bruce

I'll buy that for a dollar. And I'll tell you what... if I *was* camping with 120VAC, I'd sure as heck drive a ground stake just to be sure. Campground AC has been known to be sketchy!

[Chuckles]

at this time I don't plan on charging from the tow vehicle. I guess I can see the point about providing a return if a hot wire were to touch the frame. It's just a little extra wire so i guess I will add the ground to the frame. Should I do it from the battery or the fuse panel?

[Hogdaddy]

do yourself a favor & don't ground the frame. it will only cause headaches later .

[Shadow Catcher]

I think the point is to not rely on the frame as the negative path in wiring. When connectors corrode and they will because of galvanic action between dissimilar metals i.e. copper lug steel frame with out additional precautions you lose a good ground. This has been a perennial problem for a number of folks and something we see here with regularity.

[Dale M.]

Lot of misinformation and witches tales here.... There is no harm in grounding one side (typically negative) of battery to trailer frame, in the whole scheme of things at some point everything is grounded to mother earth and the planet does not implode/explode... You wire line telephone phone system which run on 48 volts DC grounds the positive side of their battery/power plant to mother earth, Nicola Tesla grounded the neutral side his AC circuits to mother earth....

The whole problem is some people do not understand the magic of electricity.... Or proper way to make a electrical connection....

As for grounding the chassis or connection to chassis, all you need to do is drill hole for ground connector(s) take file or sand paper or small grinder and clean paint or rust or any surface contamination till you have clean shinny metal, place a dab of dielectric grease on bare spot and bolt (screw) connection together, it's done, it's good forever..... This is what I do and I do not have electrical problems... Period!!.. I have had batteries in vehicles 6-8 years with out any corrosion on battery posts or cables, how come you say, dielectric grease....

Also use dielectric grease in trailer/tv plug and on any wire connection/splice where crimp connectors are used.... Another failure of electrical connection by corrosion is poor quality connectors and crimping tools ... You need a tool the makes a gas tight crimp and you need to use dielectric grease to keep oxygen out of connection because oxygen is main instigator of corrosion... Those $5 auto-parts crimpers that come in your 200 piece connector kits are pure junk....

Anyone that scoffs at electrical codes (NFPA) and RV industry rules about electricals ( AC or DC) is a danger to themselves and to anyone that comes in contact with their equipment...

38 years working with AC & DC power system in communications industry and only dangerously shocked once when a cord on power tool when defective....

IF you understand it and respect it, its the best friend you ever had... IF you do not respect or understand it, its your worst enemy... It's like fire, a wonderful servant but a cruel master....

Dale

[Dale M.]

It's more of an issue with 120V than with 12V but here's one good reason:

Hot Skin Issue

On the 12V side, grounding the frame is more for electrical devices that might use the frame as a return path but there's a safety issue as well. Even though there aren't any known electrocution deaths in the US from voltages lower than 48V DC, it doesn't hurt to ground the frame. The idea is to have a fuse blow if a hot wire ever lands on the frame, rather than have the frame unknowingly energized and you complete a circuit with a wrench or through the trailer hitch.

Bruce

I'll buy that for a dollar. And I'll tell you what... if I *was* camping with 120VAC, I'd sure as heck drive a ground stake just to be sure. Campground AC has been known to be sketchy!

If you do not have one of these and use it, you are asking for trouble...

Dale

[Redneck Teepee]

I agree with Dale, my 12 volt system is grounded to the trailer frame with the use of dielectric grease. Most electrical gremlins can be attributed to a bad or weak ground or grounding location. I'm not an electrician by trade, but over the years by asking and learning from those that are, I have learned the basic's and a lot of "good practice" tip's from those that are in the electrical trade.

[Dale M.]

Also one of the biggest gremlins in grounding is PAINT on bolt together frames.... To get ground to work properly you have to clean both side of frame member and apply dielectric grease where they touch (bond) to get good ground.... This is where the concept of hard wiring grounds comes from (poor ground bonding due to painted frame) and fixtures that ground through their mounting screws placed on non metallic (non ground bonded) surfaces...

Dale

[George Taylor]

Thank you Dale M for stating some things I have said and got rude comments from. I am an electrician by trade, safety is important. Do it right and the risks are greatly reduced. As for driving a stake for grounding as someone said, I would not recommend it. I will agree that some campgrounds electrical systems are screwy, but it can actually work against you. I have seen it a few times where when that is done it makes a better ground and all the issues of the system come your way. Either plug into the GFI outlet or get a cord with one built into the end.