Electrical issue

[bplotnick1234]

I posted an earlier problem that I was having with my motorhome under "Inverster problems". I don't believe that it is the inverter and I hope to get a couple of new answers with a fresh post. The synopsis of my problem was that I had no power to my coach when just running off of batteries. I have done some trouble shooting over the past few days and may have singled it out. Thanks to everyone that helped me on the other post, it helped out greatly in isolating the problem.

Okay, I got the motorhome at the house and found the box that houses the relay/isolators. With the coach and chassis switches both on both solenoids are getting power. I have been able to track down the coach solenoid by turning off the cut off switches one at a time. I noticed that both solenoids or relays have a 5 amp fuse on each side. I checked both of them and they are fine. I noticed that above the relays for the coach there is a thin box or small panel that has 6 bolts coming out of it with 3 on top and 3 on the bottom. 5 of the 6 bolts are hot. There is one on the bottom right side that has two large gauge red wires coming from it that appear to disappear under the motorhome into no mans land. This bolt shows cold when tested and has no power to it.

I used a wire and quickly jumped this bolt with one of the hot wires and it now works several appliances and lights in the motorhome. Does this mean that the block or I guess they are called buse panels or wiring panels has one bad bolt out of the 6. If so, can I just jump that bolt or move the wires to an empty bolt (2 are empty)? I just don't want to jump or move that wire and later have a major mess on my hands with melted wiring elsewhere in the motorhome. Has anyone heard of these small wiring panels going bad at just one bolt?

[deandec]

bplotnick1234 wrote:
Oh yeah, thank you for the others that replied and don't be bashful to speak up now if you have other ideas about what is happening.

Hopefully you are on the trail to success by now.

1. Do learn to post pictures to help us identify your problems. Many use the website photobucket.com to assist in posting pictures on this web site. Resize your photos to email size, using photo bucket or your computer's photo editor, to meet this site's size paramenters. There is a tutorial on RV.net.

2. Post information about your rig. Many use their signatures to inform of the key elements. This probably would not be of help on your current problem but will be in the future.

3. On my rig, there are two 300A T fuse blocks with a fuse protecting my inverter. When my batteries do not power my rig, one of them may have failed. One is located in the battery compartment and the other is located next to the inverter.
300A Class T Fuse

[enblethen]

The break should be the left hand circuit breaker. I beleive that circuit breaker is burnt out or tripped. With no easy accesss to the back of the circuit breakers, I think they are auto reset. Once they continually trip they burn out. Power comes in on lower right post, goes through the circuit breaker to the right top stud.
Extra load could be from that after market wire on the top left stud.

[bplotnick1234]

Oh yeah, thank you for the others that replied and don't be bashful to speak up now if you have other ideas about what is happening.

[bplotnick1234]

enblethen you have been a god send. Thank you for taking the time to email and reply. I will take every step that you recommended and see what happens. Personally, I believe that there has either been a crack or fuse, that I can not see, that has interrupted the power from the top right lead to the rest of the panel. I will do some more trouble shooting on Friday as the weather is supposed to improve. This website is awesome as it allows those with experience to help those less experienced. I belong to another website for 4 wheeling enthusiasts and so many issues have been solved just by brother helping brother or sister helping sister, or any other combination you might put together.

[enblethen]

Yes, all six studs should be hot if the first one on left is working.
No, you must loosen the nuts on the lower studs to be able to slide them up and out of bracket.
Yes, jumpering as stated would bypass the circuit breaker on the right.
Yes, fixing the breaker on the right should fix your issues, however I would still be concerned about the large after market wire on top right stud.
After determining it's function, you could install another circuit breaker tofeed that wire. Install additional breaker(amperage needs to be determined based on what it feeds and wire size) jumper new breaker to lower right stud with same size wire, connect after market wire to the other stud.
I wish I new how to post photos for others to see. maybe someone else can do it!

[bplotnick1234]

Okay, I think I see what you are saying. The large red wire on the top right may be a problem. The weather here is horrible right now, but in a few days I will get over and disconnect it and see what happens. I thought that the top right wire was the hot lead to this bank. If I disconnect it and the other 4 have power I guess it is not. There will obviously be no power to the bottom right two wires as they are cold already. There is a bank of wires on the other side that go to the chassis part, except there are only 4 bolts. All 4 on that side are hot.

Now that I view an enlarged picture of the wires and the bolts it looks like all of the wires should be hot as they appear to be connected on a metal plate. Is that right? Should all 6 terminals test as active and hot when the coach batteries are turned on? It also looks like I can just slip the posts out of the sleeve once the wires are disconnected. There are no bolts holding this in place as you can see if you enlarge the photo. Does that sound right? The one I jumped was the top middle (hot) to the bottom right (2 wires) and everything worked as it used to.

I am good with jumping those points and putting a breaker or in line fuse between them if that will solve the problem. What do you think?

[enblethen]

I received your photos via email
The large red wires are connected to a circuit breaker That feeds a strip of buss work. Note the copper colored studs.
The smaller green and red wires are connected to branch circuit breakers.
The studs on the bottom have a second nut that attaches the circuit breakers to a non-metallitc bracket.
The large red wire on the top stud could be a problem. It appears to be an after market installtion to feed something with large load. I would disconnect it and try to find out what it feeds. It may need a circuit breaker of it's own coming off the bottom stud.
You would need to take the back nuts loose to remove circuit breakers from the bracket. After removing the right hand circuit breaker, look closely on it for amperage. Disconnect power from batteries and from the shore power to be on the safe side.

[bplotnick1234]

Okay, I took some pics. The red wire on the top right is hot, all of the other bolts or terminals are hot except for the bottom right one that has 2 red wires attached to it. This is the one that I jumped with a hot lead and "voila", I had power to the coach. The power was right on amp wise at the fuse box inside of the coach. I used the top row, center bolt, to make the jump. Could the bottom right bolt just be dead? This little box is built in to the cover and I see no way to take it out. It is approximately 4 inches wide, maybe an inch and a half high and about a 1/2 to 3/4 inch thick. This whole box is mounted to the firewall.

Okay, I have tried to send the photos, but I can't quite figure it out. I CAN send them in an email if that is okay. If it is, just post your email address or send me an email at bplotnic@gmail.com and I will send the photos.

[jhilley]

That sounds like a bulkhead terminal post. It has connections on both sides. The one on the back that you can't see must have a fuse in the circuit. The fuses on the solenoids are for the solenoid coils. If the solenoids work they have nothing to do with the powered circuits.

[wa8yxm]

Can you post a photo of the block where you had to add the jumper,, Indicate where you jumpered.. I have suspicions but sans "eyes on" .... I'm not yet willing to type them.

[bplotnick1234]

It has gotten dark today so I will try and get those items photographed tomorrow. There is a fuse on both sides of both relays and none of them are bad if that says anything. There is sooo much wiring in this box. It makes it hard to narrow down a single thing. I am also going to try and contact Coachman tomorrow on this small panel and see if they can tell me anything.

[enblethen]

Auto mparts stores like O'Reillys or auto zone.
Locate the battery disconnect for coach, follow the wires on the output side. One of them shoiuld go to a circuit breaker before entering the rig.
Can you see a make and model of the battery control center?
Maybe post a photo?

[bplotnick1234]

Thats a good idea. Anyone know the best place to buy a breaker for this application?

[pianotuna]

Hi,

I'd go for an automatic circuit breaker instead of the fuse.

Size it to protect the wire. i.e. if it is #10 then 30 amps #8 40, #6 50 etc.