Camper conversion 12V electrics - advice

[gman88667733]

We are at the stage in our conversion where I need to look at the electrics and start running some wiring before we start on the walls. We only want a very simple 12V system really (6x LED lights, water pump, usb ports and a couple of 12V sockets)
The thing I am not entirely sure of, is what gauge of wiring do I need for those sort of bits? I am planning on using separate wires for the positive and negative feeds instead of a 2 core cable (I think it'll make it a bit simpler for me?)
The next thing I am unsure of is when wiring it all up. I am planning on getting one of the bog standard 12V switch panels with however many switches built in, a voltage reading for the leisure battery and USB + 12V ports. Do I need to wire from the fuse box, to the switches and from there, to the appliance? The fuse box has an earthing block, so I can earth it all to that.

I am a complete novice with this, so bear with me if I am way off with anything I have said..

Also, the 12V switch panels I have seen are all pre-wired with in-line fuses already. How would this be wired into my intended system? Or could I just scrap their wiring and do it as I said above (assuming that was correct)?

Cheers


( I have done loads of searches online, but most setups seem to be vastly more complex than mine, so i am struggling to find the useful info in them )

Edited by gman88667733 on Tuesday 14th July 11:13

[HarryW]

Greg Virgoe on YouTube is pretty good at explaining things. Have look here

https://youtu.be/koFg6oFs0RU

There are other electrical vids on his channel if that doesn’t cover it.

[smifffymoto]

I just put up led strips and plug into a power bank also run a fan from it.When we drive we charge everything up via a 300w plug in inverter.
There are so many options available,how about going a step in between and using a Goal zero power station.
www.goalzero.com

[HarryW]

You making progress OP? Greg pretty much covers the basics in that video.

I’d recommend thinking about some Solar to keep it topped up and a B2B charger from your alternator Too. Also if you are panelling you either run cables in conduit so you can reeve additional cables in the future or lay some unconnected spares at the same time as your initial install.





Not sure An expensive power bank is what is needed tbh, 300w is not a lot, just simple 12v system off AGM batteries.

[gman88667733]

HarryW said:

You making progress OP? Greg pretty much covers the basics in that video.

I’d recommend thinking about some Solar to keep it topped up and a B2B charger from your alternator Too. Also if you are panelling you either run cables in conduit so you can reeve additional cables in the future or lay some unconnected spares at the same time as your initial install.





Not sure An expensive power bank is what is needed tbh, 300w is not a lot, just simple 12v system off AGM batteries.

Current progress is with insulation for the walls and doors etc... I've planned the electrics now, pretty much going with what I outlined in my first post. Will be running the wiring for the lights next week so I can get the ceiling insulated.

[HarryW]

gman88667733 said:

Current progress is with insulation for the walls and doors etc... I've planned the electrics now, pretty much going with what I outlined in my first post. Will be running the wiring for the lights next week so I can get the ceiling insulated.

Good to hear, hopefully that video cleared up cable and fuse sizing, if it was in doubt.
I note no mention of a Fridge? A 12v compressor one will use roughly 450wh per day which will eat your batteries in a matter of days, hence my note to consider solar and b2b charging.

[gman88667733]

Plan is to use a 12V cool box. Don't fancy a posh one really.
It won't be used for long term use, so we aren't too worried about how good it'll be at cooling.

[HarryW]

gman88667733 said:

Plan is to use a 12V cool box. Don't fancy a posh one really.
It won't be used for long term use, so we aren't too worried about how good it'll be at cooling.

Ok, Not sure what cool box you’re getting Or it’s spec but I’m assuming you are just Going to use it as a day van then.
The reason I ask that is a cool box plugged into a cigarette lighter socket will probably run at around 5A. 10 hours of that will run a 100ah leisure battery to near flat (there’s only about 50% usable capacity).

[gman88667733]

HarryW said:

Ok, Not sure what cool box you’re getting Or it’s spec but I’m assuming you are just Going to use it as a day van then.
The reason I ask that is a cool box plugged into a cigarette lighter socket will probably run at around 5A. 10 hours of that will run a 100ah leisure battery to near flat (there’s only about 50% usable capacity).

It'll be used as a camper for a couple of nights at a time, maximum i'd have thought.
We wouldn't keep it plugged in all the time as once it'll all cool we would switch it off for a while and cycle it probably. Our layout doesn't work with having a proper fridge in as there would be no way of venting it + we aren't having a gas installation at all.

[HarryW]

gman88667733 said:

HarryW said:

Ok, Not sure what cool box you’re getting Or it’s spec but I’m assuming you are just Going to use it as a day van then.
The reason I ask that is a cool box plugged into a cigarette lighter socket will probably run at around 5A. 10 hours of that will run a 100ah leisure battery to near flat (there’s only about 50% usable capacity).

It'll be used as a camper for a couple of nights at a time, maximum i'd have thought.
We wouldn't keep it plugged in all the time as once it'll all cool we would switch it off for a while and cycle it probably. Our layout doesn't work with having a proper fridge in as there would be no way of venting it + we aren't having a gas installation at all.

Understood, rather than lifting the lid to judge internal temperature I’d recommend a Remote Bluetooth temp recorder gadget. I use one of these very handy and cheap. It’s a bit bigger than say 3 pound coins stacked together. Very handy https://www.amazon.co.uk/gp/aw/d/B08238DFWL?psc=1&...

Edited to add if after while you think you might need a fridge the 12v compressor ones do not need and external vent, just 12v. my Campervan has a Thetford T1090 fitted, you can pick them up for under £700 now. They do either floor or eye level types depending on where you want to install it.

Edited by HarryW on Tuesday 21st July 16:13

[evilmunkey]

I can reccomend gadget john too he also has a youtube channel https://www.gadgetjohn.uk/tag/12v-electrical-insta...

[HarryW]

evilmunkey said:

I can reccomend gadget john too he also has a youtube channel https://www.gadgetjohn.uk/tag/12v-electrical-insta...

Yes seconded; I follow John (and Mandy) on YouTube too, good guys......

[evilmunkey]

yeah a great pair , john had a channel with new content every tuesday called van tech tuesday that answered pretty much everything . Geeky Phil is amazing with electrics too.

[TwinKam]

We have a (three-way) absorbtion fridge and it draws nearly 10A on 12V, which would completely flatten a battery overnight. 12V coolboxes are no better in this regard. I have fitted a £2 ebay digital temp gauge to its control panel with a probe sat on the chiller bar to monitor internal temp without opening the lid, gives great peace of mind when you see -8.0C (on gas).
I've been looking at the latest gen of compressor fridges for camping, and they claim to only draw 5A peak, ie when actually compressing but, due to their thermal efficiency only run for a fifth of the time, so it works out at less than 1Ah overall. No need to spend £700 nowadays either, there are 50 litre portable top-loaders available for under £400.

[HarryW]

TwinKam said:

We have a (three-way) absorbtion fridge and it draws nearly 10A on 12V, which would completely flatten a battery overnight. 12V coolboxes are no better in this regard. I have fitted a £2 ebay digital temp gauge to its control panel with a probe sat on the chiller bar to monitor internal temp without opening the lid, gives great peace of mind when you see -8.0C (on gas).
I've been looking at the latest gen of compressor fridges for camping, and they claim to only draw 5A peak, ie when actually compressing but, due to their thermal efficiency only run for a fifth of the time, so it works out at less than 1Ah overall. No need to spend £700 nowadays either, there are 50 litre portable top-loaders available for under £400.

The £700 compressor fridge I mentioned (Thetford T1090) is 90ltr capacity with a small freezer section in it too. It runs at about 450wh for 24hrs so average is around 1.5ah. On its coldest setting the fridge (5 leds out of 5 and as measured by me) actually went and stayed below -1. Too cold for me, run it On 3/5 leds In night time mode for a temp of around 4 ( it will be nearer 360wh), but it does give you an idea of what modern compressor fridges can do. The night time button makes the compressor run slower (quieter!).

[TwinKam]

Ah OK, I stand corrected, you're talking 'built in upright' not 'portable chest'.
But in practice, whatever the layout, these newer compressor fridges are a leap forward.

[gman88667733]

Getting the split charger fitted in a couple of weeks.
I currently have a leisure battery, hasn't been used much. Only issue is, it isn't a sealed one and has a venting tube with it. Chap that is installing the split charger says not to worry about venting as I don't want to cut extra holes in the van to vent it. Apparently they start to smell really bad before they are an issue?

I am not 100% sure on this, any advice?

If it is a safety issue, I'll just get a fresh one.

[mikal83]

I'm going to piggyback on this thread as an starting on my L4H3 relay next week. Have bought everything I need and its in the garage. Batteries/TV/inverter/batt charger/cabling the lot. Looking for toilets, bloody heck wont get much change out of 350/375 for that then theres the furniture board...........up to 150 a sheet. I have designed the van with a slighty higher bed that hinges to put a small scooter in the back. Some race vans the beds so high your nose allbut touches then ceiling!! Have done 3 wiring diagrams, 12v, 230v and solar....cant wait.

[gman88667733]

It is coming along nicely. One of the rear doors is carpeted (we don't want any exposed metal that won't be covered by the cladding) ran out of carpet after that, so more is on order for the end of the week. Wiring ordered so i can start taping that in place ready for the electrics. Split charger going in next Thursday. Found a new in the box Fiamma turbo 28 for £75, so i'll be fitting that this weekend.
Batons are cut to secure to the walls for the cladding to go on, so we will start that at the weekend/end of the week too.

Slowly but surely, it is coming together!

It'll feel good once we have the wiring in and started cladding as it'll make such a visual change to the van.

[ruggedscotty]

A vented battery needs vented, no matter what he tells you, Battery will produce hydrogen. so best ensuring that its vented away fro living area so gas can not concentrate and pose an explosion risk.

AGM batterys be care full as these have characteristics that a solar panel could destroy them, they dont like being overcharged and when that happens they lose capacity - the gell in the matting is damaged through over charging.