Battery Off/On Switch

[Just Plain Jeff]

Most boats and POS coaches have a battery ON/OFF switch, which effectively disconnects the battery power from all circuits. It seems as if many conversions do not have such a chassis power switch. It occurs to me that it would be a good idea to put one in a coach if none exists in order to work on the electical system. The DC system in coach carries big amperage; at least it would be a great safety feature for the DYI kinda guy.

[truk4u]

So Jeffee Boy, does that mean my Plastic Trukster (POS in your terms) has one up on a Prevost Conversion?

What a good day in Plasticville......

[hhoppe]

Both of my Prevosts have such power switches. One for Chassis and another for coach.
Hey man you wanna buy a coach. Make you a deal your own mother wouldn't offer you.

[Just Plain Jeff]

Awright you guys.

HH: Your coach should go to Jim Chaloupka, as he hasn't had one yet, gentleman that I am....Jim?

Tom: Just because the resinmobile has such a switch doesn't mean that it works.

Y'know.

[Jon Wehrenberg]

I'll pass along some information relative to master battery switches.

The bus has battery disconnects. Generally on DDEC buses there are two, one main and a second for the computer.

I presume the house batteries have been provided with disconnects by the converter. But as an owner give your battery cables from the batteries to the disconnects or master circuit breakers a very close look. The cables between the batteries and the CB or disconnect are unprotected and if they come in contact with the bus chassis that creates a short circuit capable of melting steel. Make certain the unprotected battery cables are secured and the insulation is free of defects. I know for sure that if the positive cables come in contact with a ground such as the chassis the heat generated will cause the insulation to burn with the end result being a fire.

Please inspect your coach to make sure that cannot happen.

A second comment is particularly relevent to coaches that have been modified, but can be applicable to any coach. It is possible to have battery loads that do not go through the master disconnect switches or the main CBs. I have seen coaches with various wires going directly to battery terminals. It is possible and even probable these wires power devices that may not even have circuit protection. At the very least, these wires should be reconnected to the load side of the master switches, and then should have a circuit breaker or fuse right at the connection point.

There may be some loads that you never want disconnected, but I cannot think of any important enough to risk the coach.

[hhoppe]

Jon's correct on the power available to melt steel. I carry a "Mig Master" Wire welder in my off road jeep. It provides enough power to make good emergency welds with just one 12V battery. Think how much power 4 batteries connected to produce 24V would have. Always disconnect the ground wire first before touching other connections on batteries and the ground should be the last to be connected. Gases from batteries are explosive and will make a mess you won't forget if you still have eyesite afterward. Think of them as small bombs.