Electrical connections

[easystreet]

Taking a few extra minutes and dollars to do things up to snuff now will save you lots of backtracking later. Cable entrance fittings / clamps are cheap. Also if your unit burns down (hope that never happens) the insurance investigators wont start pointing to improper wiring as a way to weasel out of paying. Will help with selling the unit too if you decide to up grade.

I notice in the picture of the breaker panel that there is not a junction bar for the bare ground wires. You can buy these separately to add to the box. The ground bar that you would add would be attached / bonded to the housing. 
Neutrals and grounds should never be joined on the same bar in an RV. Also the neutral bar should never be bonded / have electrical continuity with the housing. Most new panels come with a screw to "bond" the neutral to the breaker box housing if it is needed for the intended application. You don't want to do this in this application. You want the metal structure of your coach to remain completely isolated from the hot and neutral sides of the AC electrical system.
I tend to think of RV's as the biggest electrical power tool you'll ever grab hold of. Happy wiring.

[Zephod]

Taking a few extra minutes and dollars to do things up to snuff now will save you lots of backtracking later. Cable entrance fittings / clamps are cheap. Also if your unit burns down (hope that never happens) the insurance investigators wont start pointing to improper wiring as a way to weasel out of paying. Will help with selling the unit too if you decide to up grade.

I notice in the picture of the breaker panel that there is not a junction bar for the bare ground wires. You can buy these separately to add to the box. The ground bar that you would add would be attached / bonded to the housing. 
Neutrals and grounds should never be joined on the same bar in an RV. Also the neutral bar should never be bonded / have electrical continuity with the housing. Most new panels come with a screw to "bond" the neutral to the breaker box housing if it is needed for the intended application. You don't want to do this in this application. You want the metal structure of your coach to remain completely isolated from the hot and neutral sides of the AC electrical system.
I tend to think of RV's as the biggest electrical power tool you'll ever grab hold of. Happy wiring.

Why isolated? I was going to earth the whole bus.

[Oonrahnjay]

... I tend to think of RV's as the biggest electrical power tool you'll ever grab hold of. Happy wiring. 

    A good philosophy.   And a good explanation of the theory of bonding and non-bonding in a vehicle, with info on the use of "house" electrical equipment in a vehicle -- thanks for that.

[Oonrahnjay]

    Hey, Zeph!  For a lot of good technical info on A/C current installation in a bus, see http://www.noshockzone.org/  -- in one of his articles, Mike shows how you can have a copper rod driven into the ground and attached to the bus chassis and still have the possibility of severe (or even fatal) shock if someone outside touches the vehicle body (if there are problems to the setup of the elecrical system or wiring damage).  He also covers "shore cords", power outlets, etc. in rigorous technical detail.  I found it very helpful.

HTH,   BH   NC

[Zephod]

My tablet died as I was editing my response.
The two earth wires visible are going to be bolted to the bracket just by them that I riveted to the case
The next two earth wires will be screwed to the case with self drilling screws.
The whole bus will be earthed.

Good point about a sleeve for the main cable. I doubt I can get a small enough sleeve for the two socket cables yet to be installed.

Actually, I need to put sleeves on the main breaker too.

I'm designing this with safety in mind.

[Zephod]

The main breaker will be inside what will become the house battery compartment. That compartment will eventually have batteries that will power internal fans, extraction fans and phone\tablet chargers.

The plugin for the side of the bus will be this http://www.ebay.com/itm/271909878145 and it'll probably not be plugged in via an access hatch on the side but from an underbody point. That keeps the rain off it! I might just plug a blank into it to keep it clean during travel if I don't out if behind an individual hatch.

[Zephod]

Well, I didn't get enough done. I'm sore from being under the countertop in weird contortions.

Both of the remaining socket boxes are fitted. The over code 30A cable is a tricky beast to handle! I've got one length as far as the breaker box but that's as far as it goes. I couldn't find my hacksaw with my flashlight!

I did fit strain relief collars. That was a good suggestion. I'm thinking that by next weekend the electrics might be completed.

[scanzel]

Just curious but why are you running 10/2 for all your wiring and then you stated your putting a 15a/ 20a receptical on the end of it. 15amp run 14/2, 20amp run 12/2. No need to run 10/2. The average home has either 15 or 20 amp circuts. Larger if running electric stove, large rated air units or central air. On a bus you are not going to have a voltage drop in such short runs. Take a look at what your plugging into the receptical what it is drawing in watts. 15amp max 1500 watts, 20amp max 2200 watts. And never run them at max amp/watts.

[Iceni John]

The main breaker will be inside what will become the house battery compartment. That compartment will eventually have batteries that will power internal fans, extraction fans and phone\tablet chargers.

As a general rule it's not recommended to have any electronics in the same area as vented lead-acid batteries, because the acid fumes given off by the charging batteries can damage or corrode other things nearby.   Whether a breaker panel would suffer or not, I don't know.   You should also consider putting vents in the battery compartment to let out any build-up of hydrogen gas  -  these vents should be high, the opposite of propane vents that are low.   You also wouldn't want a spark from the fan motor to reach any hydrogen there!   At the least, turn the batteries' vent caps so they don't point straight at the cable lugs, and use tinned lugs to lessen corrosion.

John

[eagle19952]

Just curious but why are you running 10/2 for all your wiring and then you stated your putting a 15a/ 20a receptical on the end of it. 15amp run 14/2, 20amp run 12/2. No need to run 10/2. The average home has either 15 or 20 amp circuts. Larger if running electric stove, large rated air units or central air. On a bus you are not going to have a voltage drop in such short runs. Take a look at what your plugging into the receptical what it is drawing in watts. 15amp max 1500 watts, 20amp max 2200 watts. And never run them at max amp/watts.

I believe he said that he used 10/2 incase he wanted to upgrade.
bigger is allowed, smaller is not.

[Zephod]

I'm using 10-2 just in case I want to run something 20A off the 20A sockets and give myself generous room by using 30A cable.

My main breaker is 30A but the cable is 55A which gives room for expansion.

[Zephod]

As a general rule it's not recommended to have any electronics in the same area as vented lead-acid batteries, because the acid fumes given off by the charging batteries can damage or corrode other things nearby.   Whether a breaker panel would suffer or not, I don't know.   You should also consider putting vents in the battery compartment to let out any build-up of hydrogen gas  -  these vents should be high, the opposite of propane vents that are low.   You also wouldn't want a spark from the fan motor to reach any hydrogen there!   At the least, turn the batteries' vent caps so they don't point straight at the cable lugs, and use tinned lugs to lessen corrosion.

John

There will be plenty ventilation. I'll be installing a metal compartment made from angle iron with the metal sheeting from an old fridge acting more as a splash guard than anything else.

Like as not, there'll just be one battery. That'll power tablet/phone chargers and extraction fans. That's all.

[TomC]

You better read up on RV wiring. If you have a generator, it needs to be grounded to the chassis of the bus-unless you want a wondering short to happen. If there's a short with no place to go, you could be zapped. You want the chassis of the bus to act like the ground pulling the electricity away to the generator, or when on the power pole, directly to the ground. Good Luck, TomC

[Zephod]

My electrics are done. All 120v plugin for now.

Sent from my Nexus 7

[Zephod]

Just before I finished the wiring.

My temporary main breaker setup - until I rebuild the compartment.

Sent from my Nexus 7