Almost burned up my bus (or at least the electrical)!

[belfert]

My bus has four group 31 batteries in a unique configuration.  There are about 16 different connections to the four batteries.  Several terminals have three connections.

I removed the batteries for replacement back in May.  I carefully labled all of the connections and made a numbered diagram.  I finally installed the new batteries Monday evening.  I got down to the end and something didn't seem right with the last connection so I went inside to find the wiring diagrams.  When I went inside I could smell electrical burning so I ran back outside and started disconnecting everything in a hurry.

I was very lucky there was not a electrical fire.  I did find a cable I misread and hooked up wrong.  I am guessing I fed 24 volts into the 12 volt side of the system.  Luckily, everything works including the DDEC and WTEC.  I can't find anything that got fried so far.

[HighTechRedneck]

This may or may not have had anything to do with what you misread, but it happens to a lot of folks that number their home stereo/video wires.  Either don't use the numbers 6 or 9 or else always draw a line under the 6 and under the 9 to aid in reading the right side up when you put it back together.

[belfert]

I somehow put the #1 wire on something else.  Only 8 studs on the four batteries so no issues with 9s and 6s.

I have no idea how I read it wrong.

[oldmansax]

Do yourself a favor:

Buy enough electrical junction blocks to wire all the wires together with only one going to the battery terminals. That makes for better connections plus less chance of mis-connecting something. I know you may not be able to do it now but it should be on your list. The PO of my bus had wires everywhere. I am still sorting them out.

TOM

[belfert]

Not that it matters, but this is the way it was wired from the factory.  Nobody changed anything.

[buswarrior]

Besides the advice to wire all your 12v to one junction and all your 24v to another and then a single wire to each battery point required, you want a cut-off switch in each of the two lines.

Easier to stop the fire by throwing two switches than undoing wires, which will be red hot...

And leaving the switches off while the coach is in storage removes all chance for parasitic loads messing with the batteries.

happy coaching!
buswarrior

[niles500]

Brian - Don't you have a disconnect switch on your bus ? I didn't think any came without one.

[belfert]

Brian - Don't you have a disconnect switch on your bus ? I didn't think any came without one.

Certain stuff such as the computers and a few other things get power regardless if the battery disconnect is on or off.