cracker39 wrote:I have read so many posts about the electrical systems and it seems that there are conflicting statements and I have some questions to clear up my consusion.
1. Tail/stop lights: Why bother with frame grounding for my tail lights if I am running a ground wire from my tow vehicle to my trailer lights? All tail lights will return the ground to the tow vehicle's frame. (I have a 5+1 connector with wires for 1) tail lights/clearance markers 2)stop lights 3) left turn 4) right turn 5) ground. That leaves me one for backup lights if I want to use them.)
2. I have seen lots of diagrams where the 120VAC shore power was not frame grounded, and one diagram that did have a frame ground for the 120VAC. Do you ground the 120VAC to the frame or not? In a house, there is no "frame ground". All grounding is done via the ground wire back to the circuit breaker box ground bar. I plan on using a breaker box with 4 120VAC 15 amp breakers in it. One for the Air, one each for front and rear 120VAC outlets, and the last one goes to the AC/DC converter.
3. If you do ground the 120VAC to the frame, do you also ground the 12VDC for the trailer fan/lites/outlets to the frame? If you are running ground wires for all 12VDC usage back to a common ground block, then to the battery, is the frame ground still necessary?
cracker39 wrote:But, regarding the 120VAC grounding tp the chassis, I would think that applies if there is metal in the cabin construction (i.e. skin, matal framing, etc.), that can be shorted. But my cabin is all wood and I unless I am wrong, wood doesn't conduct electricuty. There will be no metal except for screws attaching skin and cabinetry to the wall framing and those would never come in contact with the 120VAC or the 12VDC. In other words, there is no chance of the 120VAC being contacted by the occumant except from an outlet on the wall. I think a lot of the rules of 120VAC grounding are for conventional trailers with skins and/or frames made from metal. I'm no electrician, but here again, I am only trying to use logic and commoin sense (if I have any left that is).
Steve_Cox wrote:Hypothetically writing. On your AC power the neutral and the ground are bonded together and the ground is bolted to the frame. You go to "Poppy's by the Tree" campground and it turns out Poppy is an amateur electrician. You get the campsite with reverse polarity (all Poppy's campsites have reverse polarity). You set up and plug in your power cord. <B>You go to take your bicycle off the tongue mounted bike rack and suddenly you find that you can't let go of the handlebars because you're getting about 112 of the 117 volts available right into your continuously constricting muscles in your hands. Don't you wish for a split second you hadn't tied the ground to the frame</B> as you feebly jump into the air to get your wet bare feet off the damp ground and break the circuit?
Steve in St Augustine
Steve_Cox wrote:PS - I'm building a woody teardrop and have a ground wire to my frame. <B> I also have a "reverse polarity " warning light on my AC electrical panel. </B>There are lots of Poppys out there in the world.
cracker39 wrote:Steve_Cox wrote:PS - I'm building a woody teardrop and have a ground wire to my frame. <B> I also have a "reverse polarity " warning light on my AC electrical panel. </B>There are lots of Poppys out there in the world.
Stave, did you buy the polarity warning device or make it? I found one in a catalog for $29.49 that plugs into an AC outlet and monitors voltage as well as testing the polariry. They also have plug-in DC voltage monitors for $15.79 which is about as cheap as building one with parts from AllElctrics.com. I haven't gotten as far as designing my panel (or deciding if I even need a panel with these plug-in devices) or just where I'll mount it yet. Being to the point where I install electrics is several months away. I haven't even started to construct my chassis yet.
IraRat wrote:One of two things is going to happen to me:
My head is either going to explode from all of this electrical talk that I'm totally ignorant about. Or I'm going to be the first one on this site to die in my sleep from a TD electrical fire. (And man, wouldn't THAT be embarrassing!?)
Steve, please look at this, which I plan to order Friday:
http://www.boatersworld.com/webapp/wcs/ ... escription
I plan on doing just 120, so if I run grounds to all devices, and this is grounded to the shore station via the connector, do I have to ground anything to the frame?
PLEASE give me the easy answer or else that head is going to explode.
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