12v 'smoke' missing

[DiverRay]

What Should Be:

The wires run directly to each light:
+12v ====(L)====(L)====(L)====(L)====(L)=== Ground

Check/fix the connections at the first light and Robert is your mother's brother.


What You Have Described:

The wire may run through up to five hidden junctions and tee over to each light:
+12v ====T(L)====T(L)====T(L)====T(L)====T(L)==== Ground

Scott, The wires ARE NOT as you think they should be. IF they were, one bad light, NO LIGHTS (series circuit ) They NEED to be in a parallel circuit so if one light fails, the rest stay on. Yes, there are probably "T" connectors, or worse, scotch connectors! for each light. Brant need to get to the connection for the first light, and see what is wrong with it.

[3Phase]

Yep, I know they're wired in parallel like house wall sockets and lights and not a cheap string of Christmas lights but it's difficult to show wires with ASCII text. The = is supposed to be two wires....

Anywho, it doesn't matter: series or parallel lights will not work if power doesn't get to the first socket or light.


I can believe the Scotchlocks because what's described is the wires run like a power/ground bus through the walls and ceiling with the loads/returns run from junctions or tees. If that's what they (the manufacturer) did I'm surprised there's actually a ground wire and the lights aren't just tied the nearest handy piece of metal like running lights.

.

[motoman]

Both pages of manual have top views of trailer(like the roof blew off). One is diagrahm of 110v system. The other page is of the 12v system. Both top-view diagrahms have just one line drawn for each circuit coming from fuse panel, with each zig-zaging line in top view crossong thru a lite in that circuit. The wires dropping thru ceiling of lite in question is the FIRST one in that circuit of five lites. Rest of those five lites work. Positive wire out of ceiling of 'guilty' lite is the culprit that won't carry 12v under load....drops to 1.4v.
Diagrahm is NOT like one of an electrical schematic, like the one of our XS11's. In other words, no positive/negative lines shown for wiring. Just one line as to its location and each lite location it passes through, with a direction slice thru line every so often showing its direction of travel, from-to type of thing.

Initially Scott, volt meter showing 12 point whatever volts across those two wires, and then wondering why new lite would'nt light up was what first brought my questioning here. With everyones help/input, narrowed it down to which wire(positive), that wasn't happy carrying the 'smoke'.
Problem now being, short of ortheoscopic surgury, and not doing any damage to ceiling, is possibly a not yet seen/heard way I may be able to access that wire other than the one inch hole where wires dropped thru and then hole dobbed closed with white silicone looking material. Rectangle light attaches flush, covering wires and plugged hole.

Hope that maybe cleared up the mud a bit for ya'.

[XJOK2PLAY]

Motoman,
Riding therapy is better than strong medicine or laughter, in my book!
Only riders truly understand it!

True, 12V tends not to "get ya" like 120 v will, but it never ceases to amaze me how hot 12V can get, and how fast it can happen... just like 120V.

120 V receptacles... Hot (120V + power)( black, usually,) neutral (- power, returns back to the origination point like the generator at the power plant.) and bare or green insulated ground. This is the framework earth ground. Returns to the earth ground rod. Serves 2 purposes; one for BCSC (branch circuit, short circuit) ground fault return path to ground to cause the OC (overcurrent) device (breaker) to trip if a short occurs from hot to chassis or framework ground path, and to also serve as a pathway to bleed off lightning back to the earth should the wiring network take a strike.

Most folks don't really understand the difference between neutral ground and the bare earth ground. They really get confused in house panels when they see both sometimes terminated on the same strip. It used to confuse me when I first started working in electrical with my dad as a young boy. It simply looked like a waste of wire and redundant to me then! Lol now I know better...
... and now you do, too! HTH a bit.
Hope you find the bad spot soon, bro! Hang in there... I feel your pain, believe me! Lol
Bob

[XJOK2PLAY]

Now... Here's another bit 'o info...

As for the electrical power corded service that feeds an RV from a power ped outlet...
Say you have a larger RV that has A/C units... They require a 50amp, 250 V service. 4 WIRE cord. In the RV panel, the white neutral wire, (and all 120V neutrals from branch circuits) have to be separated from the grounds.
If they bond together, you can get shocked at times by touching any part of the metal framework! How? Neutrals can, at times, carry trace voltage. Certain devices can create this trace voltage on the neutrals... like ballasts, transformers, motors, compressors, etc. this is known as a 3rd order distortion called harmonics. But, what it means is... If you make the mistake in a mobile home or RV panel and bond both neutrals and grounds to the same strip... you can get shocked! They have to be isolated from one another, with separate service wire feeds... Hence a 4 wire service, instead of a 3 wire. Newer slab built homes today per NEC must also use 4 wire circuits.
Now... If you only have one breaker box in a slab built, wood framed house, the neutrals and grounds can bond together on the same strip in the panel. But... If you have a second breakerbox, say on the other side of the house... All neutrals and grounds in the second panel must be isolated.

Clear as mud?
Guess what, Brant... This is the easy stuff I gotta know. Oh... And every 3 years, they change a thousand things in the new code! The hardest for me is all the algebraic chain calculations I have to figure all the time for things like voltage drop, etc. did I also tell ya the last math class I took in school was Algebra 1 in the 9th grade?? Yet, I can do it, and amazingly come up with the right answers! (Usually.....)

So now you know why sometimes I struggle with remembering my own name! lol
Hope all this crap made ya laugh.
Bob

[motoman]

Now... Here's another bit 'o info...

As for the electrical power corded service that feeds an RV from a power ped outlet...
Say you have a larger RV that has A/C units... They require a 50amp, 250 V service. 4 WIRE cord. In the RV panel, the white neutral wire, (and all 120V neutrals from branch circuits) have to be separated from the grounds.
If they bond together, you can get shocked at times by touching any part of the metal framework! How? Neutrals can, at times, carry trace voltage. Certain devices can create this trace voltage on the neutrals... like ballasts, transformers, motors, compressors, etc. this is known as a 3rd order distortion called harmonics. But, what it means is... If you make the mistake in a mobile home or RV panel and bond both neutrals and grounds to the same strip... you can get shocked! They have to be isolated from one another, with separate service wire feeds... Hence a 4 wire service, instead of a 3 wire. Newer slab built homes today per NEC must also use 4 wire circuits.
Now... If you only have one breaker box in a slab built, wood framed house, the neutrals and grounds can bond together on the same strip in the panel. But... If you have a second breakerbox, say on the other side of the house... All neutrals and grounds in the second panel must be isolated.

Clear as mud?
Guess what, Brant... This is the easy stuff I gotta know. Oh... And every 3 years, they change a thousand things in the new code! The hardest for me is all the algebraic chain calculations I have to figure all the time for things like voltage drop, etc. did I also tell ya the last math class I took in school was Algebra 1 in the 9th grade?? Yet, I can do it, and amazingly come up with the right answers! (Usually.....)

So now you know why sometimes I struggle with remembering my own name! lol
Hope all this crap made ya laugh.
Bob

.........and I DID remember to turn LEFT.
It's a 30A service(has a switch panel choosing either AC or MICROWAVE).
Just happy issue is not with the 120v side of service. Least in this part of country, corrosion/rust are not a normal issue, so that helps!

[BA80]

Now Bob, how is it you know all this algebra and $hit but you can't get your GPS setup to work right.

[ViperRon]

There is one good old for sure way to find an issue like this. These intermittent connections can be near impossible to trace with a meter because they are so grey. This does not work on circuits with electronic devices attached it only works when circuit is reduced to straight wire using low voltage. On simple wiring you can disconnect what is working to ensure its not effected. Pull the lights that are not damaged out of the circuit and go up the line dead sorting the connections momentarily. What this will do is burn out a connection where the wire is partially crimped or broken. and leave a smoke mark where there is an oxidized connection and most likely create a solid open condition to troubleshoot to the bad spot. If it does not burn out the connection it will most likely turn the wire that has the problem a new overheated color.

Years ago I discovered this when my former wife give me several bunches of Christmas lights to troubleshoot and repair. Once you get aggravated enough you resort to drastic solutions and I can guarantee it will give you a solid thing to replace next.

[Jerry]

Hmmmm...I was working on my RV, trying to fix the bathroom blower, no schematics to refer to. Ended up taking power off the nearest light and running a bit of wire over to the blower switch, now both the light and blower work fine...

Insulation is fiberglass batt, used a fish wire to run the new wire in place, removed the inner vent liners to get access to the area under the roof, wasn't that bad of a project but did take a little time.

[3Phase]

I kind of like Ron's solution; used something similar as-necessary to find squirrels, hidden/unmarked 'breakers and fuses... but it's not my R.V.!

.

[ViperRon]

Worked great on them darn Christmas lights I never had to worry about wasting time on crap like that again.

[motoman]

Well, since it's the positive of the two wires in that one light(rest work in that circuit), and not the more easily remedeed ground wire, could always revert to one of those stick-on battery lights for dark places and to better see the closet skeletons.

[3Phase]

Hey, Brant that's a great idea!

Ditch the flaky 12V fixture with its stone-age Light Emitting Resistor; cap the wires and cover the hole in the ceiling with a few of those stick-on LED lights that run for 10 years on a couple of AA batteries. Voila!

.

[XJOK2PLAY]

Now Bob, how is it you know all this algebra and $hit but you can't get your GPS setup to work right.

'Cause I made the mistake of listening to my friend Tim, who talked me into getting a cheap android 7" tablet, downloading GPS software... what a mistake!

Ditched that effort as soon as I got home!
I tried 5 different softwares. They were all crap.

Tried the TomTom Rider next. Great hardware, suck software. Total failure again.
Went back to Garmin. Works ok now.

Finally "did the math".... Lol