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Discussion Starter #1 (Edited)
VERY IMPORTANT!!
I was happy to place the various components in their locations, but I was NOT happy to wire it all together. I employed a local auto electrician to wire it all up. (See the links tab, mechanical for the name of the company that wired my van.) That way it was done properly. If you are in any way unsure about vehicle electrics, PLEASE get this stuff done by a professional.

Before I started my conversion, I knew absolutely nothing. I read alot of stuff about the electrical system before I chose what components to get. I still didn't get it quite right. (split charge diode - didn't work :bhd)I decided to keep it simple. You can spend an absolute fortune on this stuff.

My whole system goes something like this:
1. From the alternator, the circuit to the main starting battery is untouched.
2. At the fuse box in front of the battery, a feed is taken from a spare 50 amp fuse, using 170 amp cable, into the Voltage sensing relay. This has a negative lead & two battery teminal posts. The input on the VSR is connected to the main battery.
3. The output of the VSR is taken to the rear of the van into my electrical cupboard. This is also 170 amp cable, which is fused at BOTH ends (VSR & Isolating switch) with a 40 amp fuse.
4. The 170 amp cable is wired into a quick release isolating switch, the sort used to isolate the electrical supply on racing cars.
5. The output post of the isolating switch is taken from that onto the 12v 113ah leisure battery positive terminal.
6. The negative terminal on the Leisure battery is wired with 170amp cable onto the bottom seat belt captive nut on the C-pillar. This has had paint removed around the hole to make sure a good connection. Also the negative terminal on the battery is taken to a slave terminal on the inside of the cabinet. This removes the spagetti from the battery.
7. The positive terminal on the battery is then wired onto another isolating switch, to enable total isolation of the battery from the van, should this be required.
8. The isolating switch has a power wire running to the circuit breaker/switch panel. This has a common 12v input to six RCD circuit breakers of the following values: 1x 6amp, 2x 8amp, 2x 10 amp 1x 15amp.
9. The switch panel is wired to the following circuits: 6 amp - lights, 8 amp - water pump, 8amp - blower/fan for 12v compressor fridge, 10 amp - spare, 10 amp - 12v compressor fridge (WAECO CR50E), 15 amp - 12v cigarette lighter sockets.
10. All power wires from the switch panel are run to the relevant appliances/circuits.
11. All negative wires are run to the slave terminal.
12. I also have a 240v 600w sterling inverter wired to the main circuit side of the power isolating switch. NOT the battery side. Negative wire goes to the slave negative post.
13. The output of the inverter has a 13 amp 240v plug, wired to a junction box, which splits the supply between two double flush stainless steel 240v sockets.
14. I also have a 12v sterling battery charger, which suppllies 10 amps when the battery is fully charged. This is wired to the same post as the inverter. Negative wire goes to the slave negative post.
15. The battery charger is plugged (with 240v 13 amp plug) into a tent type 240v hook up. This has the orange wire running through the grommet below the drivers side rear light & runs to a plug hidden behind the rear passenger `pretend' foglight. I just unclip this to access the plug.
16. I can unplug the battery charger. unplug the 13amp plug from the rear of the inverter & plug the 240v system into the 240v tent type hook-up. This will give me a true 240v system.

I hope all of that made some sense.

Here are some pics of my system.






The items you can see are:
On the rear of the cabinets:
1. 2x isolating switches
2. 1x 240v stainless steel double socket
3. 2x 12v cigarette lighter

Inside the electrical cupboard:
1. 1x 113ah 12v sealed lead acid numax battery in double box. The lower silver box is a fabricated 3mm thick fully welded aluminium box, bolted & screwed to the van chassis. The box is then packed & lined to allow a snug fit for a plastic liner. This will allow the battery to leak & not damage the cupboards/van chassis. The battery is placed in the plastic box & packed with timber. There are also 2x roof rack straps which run underneath the aluminium box & over the top of the battery to hold it in place.
2. 1x Sterling propower Q quasi sine wave 600w inverter (red & black thing - usually mistaken for an amplifier)
3. 1x Sterling probudget 12v battery charger/10 amp power pack (Blue box)
4. 1x slave negative post. This has the higgledy pigglety black spider wiring running to it.
5. 1x Tent type 240v hook-up. This is usually used for tents, not camper vans. It does have 2x RCD's in it.
6. 1x 240v Junction box (white circular item on back wall)
7. 2x 12v cigarette lighter sockets (rear of)
8. 1x 240v double socket plasterboard mounting box.
9. Thick red cable running above the rear of the isolating switches, to a fuse holder containing the 40amp fuse. This then runs to the isolating switch.

Front of the top cupboard:
1. 1x 240v double stainless steel flush socket.
2. 2x 12v cigarette lighter sockets.
3. 1x 12v circuit breaker switch panel.

In the engine bay:
1. 1x Voltage sensing relay 125amp, by BEP Marine. See instructions for this here.
2. 1x 40 amp fuse in a clip holder.
3. 170 amp wiring for split charging system.

My suppliers of various bits of kit:
12v leisure battery, 12v charger, 240v inverter, 12v circuit breaker panel, 12v wire (not charging wire) 12v isolating switches, 12v sockets, 12v WAECO CR-50E compressor fridge:Midland Chandlers Penkridge.
12v Voltage Sensing Relay: Devon 4x4 South Molton, Devon.
12v Water pump (& sink, tap, water containers, piping): Concept Multi-Car Kent.
12v charging 170amp cable, 12v negative 170amp cable, 40amp fuses, large fuse holders: Vehicle Wiring Products Ilkeston, Derbyshire.
240v tent type hook-up & blue socket/plug (to make an extension lead out of the offcut orange wiring) Towsure Birmingham.
240v Stainless steel double sockets, double plasterboard mounting boxes, junction box, 240v 3-core wire, 240v 13amp plug: B&Q Wolverhampton.

I wanted to have a system that should fulfill my needs of weekend van. The single most expensive bit was the fridge. It was still cheaper from Midland Chandlers than anywhere else I could find. The only down side was that I had to collect.

Phew! That took some remembering.T:
Jurasik :D

Edit: Wiring Diagram below added:
 

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Thanks Jurasik

A fantastic post, just what I wanted - the wiring diagram is so clear, along with the description of what has been fitted. I am now able to go to an auto electrictian sounding like I know what I'm talking about; there's a first time for everything. Great looking van, by the way.
 

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Brilliant post, clearing a lot up for me.

I'm about to start my project. Not having a mains hook up so it's a simplified version of this.

what is the small black wire coming from the VSR? Can't see it on the diagram? Just earth? Or sensor?

Also by running the VSR input form the fusebox is this just saving having to connect directly to the starter battery terminal?

Trying to get my head around wiring :confused:

Thanks! T:
 
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How does the VSR decide when to charge and when not to, or does it just do it whenever the engine is running? I assume once the optimum voltage is reached it isolates the system, hence voltage sensing?
 

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this is really helpful, been slowly getting my head around what i need to do/buy to wire my van up. the wiring diagram is superb.

this post should be at the top of the page whenever anyone searches for split charging, mains hook ups, inverters etc (as i've been doing for the last hour or so)

thanks again
 

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Hi Jurasik,

Thanks for top post. I have pretty much copied your wiring diagram and have the same dual sensing relay set up.

Over last summer I drove this van round South France, Italy and Switzerland. The 12v compressor fridge was giving the leisure battery some hammer but all OK as I had my leisure battery charger running when I was at the camp site electric hookup.

My Q is this:

If the leisure battery was completely discharged and the vehicle battery fine, how is the leisure battery charger prevented from over charging the vehicle battery as the two batteries will be connected in parallel due to the dual sensing VSR relay.

I am asking this as I drove this van straight back to the UK and parked it up. I have since started getting her ready for camping to find that the voltage regulator on the alternator had blown up and the fairly new (2yrs) old Bosch vehicle battery is buggered.

Has anyone else had this problem?

Thanks

Timo
 

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Discussion Starter #18
Hi Jurasik,

Thanks for top post. I have pretty much copied your wiring diagram and have the same dual sensing relay set up.

Over last summer I drove this van round South France, Italy and Switzerland. The 12v compressor fridge was giving the leisure battery some hammer but all OK as I had my leisure battery charger running when I was at the camp site electric hookup.

My Q is this:

If the leisure battery was completely discharged and the vehicle battery fine, how is the leisure battery charger prevented from over charging the vehicle battery as the two batteries will be connected in parallel due to the dual sensing VSR relay.

I am asking this as I drove this van straight back to the UK and parked it up. I have since started getting her ready for camping to find that the voltage regulator on the alternator had blown up and the fairly new (2yrs) old Bosch vehicle battery is buggered.

Has anyone else had this problem?

Thanks

Timo
As I said in reply to your PM regarding this issue, you are the first person to report such a problem.
This has already been discussed in your thread here. I also said to you in the PM that with the isolator connecting the batteries together, the charger takes a long time to charge both batteries, but will do so eventually. I said that I tended to (in the rare occasions that I do use the charger) disconnect the starter battey with the isolator, so that the charger only charges the leisure battery. That is one of the reasons to fit the isolator.
I feel in my bones that your volt regulator issue & main battery problems are not connected to the use of the VSR.
 

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Discussion Starter #19
Hi Timo.

I can only comment from my own experience with the charging.
I have done exactly the same as you (dead leisure, reasonably charged starter) & used the sterling battery charger (with both connected) to charge up the leisure. I have done this twice & it took a long time (over 2 days) on both occasions to recharge the leisure battery. The main starter battery/alternator suffered no ill effects on both occasions. I now isolate the starter battery when I am using the battery charger, simply to speed up the charge time.
 

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Remember to keep 230v ac systems seperate from 12v dc systems......this is a good post :ILU:
Yeh good post, i`m looking to do something similar, there is one point i`m not sure about with your wireing diagram, can you have the output from the inverter on the same line as 240V hook up?, when your hooked up can this damage the inverter or is it dangerous?
sorry if this is obvious
Thanks
Tom
 
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