Wiring Fridge,Compressor,Fusebank

[Smoothrun]

Hi All

Im looking at wiring up my GU now that I have my Aux Batt set up, Ive got a few options and not exactly sure what the best way is to go about it, my Autoelec knowledge is minimal to say the most, so thought it would be a better idea to get some feedback from those with more experience than myself,

Heres what im considering all from Aux Battery

6B&S Run + & - from Battery through firewall to a 6,8 or 10 space Fuse bank with a 40A inline fuse next to Battery, Fuse bank mounted either under dash or preferably to rear drawer wing space.

Compressor
ARB CKMA12 from fuse bank 6B&S run + & - to compressor using 40A inline fuse, also mounted in rear wing.

Fridge
Engel, Do I just run it seperately to the fuse bank using a inline fuse, if so what size considering the fridge runs about 1.2A to 2.4 A, understanding they have a thermal fuse I just cant find in my searching a fuse size or more importantly a best option to take when wiring up a fridge. Im also considering a switch to turn on and off, but just as easy to pull it out during the week whilst at work, and plug it in when I do me trips

All this said and done Ive also heard that some people run an earth from the chassis as there have been issues in the past due to Battery earth being connected to the body only, as stated above im looking at running a Negative from the Battery to the fuse bank in the back, would this be enough or have some of you taken the Chassis approach also.

I hope I havent put too much into a single post but it is all relative and im hoping to find a best option and have a go at it myself.

Appreciate any input you may have,

Cheers

[MudRunnerTD]

I would run it straight to the back and install your sub board in the rear. Put a fusable link under the bonnet for the wire running to the back. I have run a single 35mm2 wire to the rear as the supply as there is then no voltage drop and I can run whatever I like. Including the option to wire up an Anderson plug at the tow bar for the camper trailer charge.

Swap your fridge plug for an Anderson Plug.

I have a fridge in the back permanently. I have a second Anderson plug outlet for a second fridge when touring if I want it.
I have an Anderson plug to hook up a 1500w pure sine wave inverter in the rear too.
I have an ARB hi output compressor permanently wired.
I have running water via a 12v pump at the rear.
I have a rear work light
I have multiple led lights to the rear.
I also have multiple charging point a at the back for when at camp to run lead lights or to charge the iPad etc.

The sub board works great and there is no voltage drop.

Earth you second battery to your motor and your chassis. Earth your sub board to the chassis.

That's what I have done and works a great.

[sooty_10]

I have very similar to what you suggested, I ran 6 B&S twin core from aux batt to a 75amp circuit breaker just at the battery then to an engine bay fuse block, it then continues through the firewall and down to rear and then have a fuse block in the rear side wing of my drawers, also have my compressor in the side wing. I run my fridge, lift pump, rear lights etc all from that fuse block. The compressor has it's own inline 40amp fuse. I have some switches up front and used 7 core trailer wire to run it to the rear where I have relays to control fridge, compressor etc.

[lucus30]

I have very similar to what you suggested, I ran 6 B&S twin core from aux batt to a 75amp circuit breaker just at the battery then to an engine bay fuse block, it then continues through the firewall and down to rear and then have a fuse block in the rear side wing of my drawers, also have my compressor in the side wing. I run my fridge, lift pump, rear lights etc all from that fuse block. The compressor has it's own inline 40amp fuse. I have some switches up front and used 7 core trailer wire to run it to the rear where I have relays to control fridge, compressor etc.

I should have looked at your setup as I want to do something similar. How did you split off the 6 b&s? Did you use a bus bar or something ?

[Cuppa]

Do as you’ve suggested, plus add MR’s suggestion for an Anderson plug on fridge.

I’m not sure what current your compressor draws, but if it’s anywhere close to 40 amps, then putting a higher amp fuse at the battery would be worthwhile otherwise you run the possibility of blowing it if you ever run something else at the same time as the compressor.

Unless you have a very small & super efficient fridge it will most likely draw more than you suggest. Your figures look more like ‘average’ draw to me (i.e. taking into account the off cycle, & averaging total use throughout the 24 hour period & dividing by 24. I’d guess when running 3.5amps to 5 amps would be more likely. A 7.5 amp fuse should suffice. If it blows on start up, put a 10 amp one in.

Something worth considering is to use circuit breakers rather than fuses. Over time & in mobile situations like ours where vibration is part of the equation they are safer & more reliable. Lots of instances of blade fuses becoming high resistance over time & melting, with fire being a potential result. I don’t know why but this seems more common in the multi fuse blocks. Loads of people will tell you that they have used these multi fuse blocks without problem.... and they have, but I have seen & heard of plenty occasions where catastrophe or near catastrophe has occurred. (From melted fuses & wire insulation to complete loss of vehicle). Circuit breakers come in a number of ‘flavours’. I like the type that are switched, as they double as circuit protection & on/off switches, & don’t require spare fuses to be carried.

If you want to stick with fuses then this sort of ‘resettable fuse’ gives a little extra convenience. They are available in a variety of amperage values.
http://www.ebay.com.au/itm/NARVA-55730-30A-CIRCUIT-BREAKER-REPLACES-STANDARD-BLADE-FUSE-BATTERY-/221498871612?pt=Caravan_Parts_Accessories&hash=item33925c8f3c

[the evil twin]

No way I would change the Engel fridge plug for Anderson.

The Engel factory plugs are much better than any others on the market even including Anderson style so I strongly recommend you get an Engel socket and wire that in.
You simply screw off the backshell on the ciggy plug adapter "nose" on the factory Engel plug and that leaves a two pin plug and backshell.
Push the plug into the Engel socket and the backshell then screws onto the Engel socket and the plug will not come out.

I convert all my 12 volt fridges (reccy or work) to Engel plugs for that reason

If you ever need to use the Fridge elsewhere simply screw the Cigg Plug adapter back on to the Engel plug.
It is more likely the other source you will want to use is a Ciggy Plug than another Anderson

[Cuppa]

I’ll bow to ET’s experience on the fridge plug. I’ve never had an Engel, & assumed that all fridge plugs were much the same. For those folk who do change their (non engel) fridge plugs to Anderson plugs I suppose it may be a wise move to make up a short adaptor cable with an anderson on one end & a ciggy type plug on the other if there is a possibility of needing to plug the fridge into someone else’s vehicle.

[sooty_10]

I should have looked at your setup as I want to do something similar. How did you split off the 6 b&s? Did you use a bus bar or something ?

The fuse blocks I used are from Jaycar and they had a decent sized stud for the power input. I simply used battery lugs crimped onto the 6 B&S and bolted them to the fuse block terminal.

49504

[the evil twin]

I’ll bow to ET’s experience on the fridge plug. I’ve never had an Engel, & assumed that all fridge plugs were much the same. For those folk who do change their (non engel) fridge plugs to Anderson plugs I suppose it may be a wise move to make up a short adaptor cable with an anderson on one end & a ciggy type plug on the other if there is a possibility of needing to plug the fridge into someone else’s vehicle.

Need to say a quick sorry, Cuppa... just reread my post and it came across a bit uuuummmm terse and certainly wasn't how I meant it.

For the record I agree with 99% of the info prev posted in the thread.
The fridge plug info is just a very small part of the overall project.
It happened to be just after Cuppas post is all.

Many, many people are not aware how good the Engel plugs are or that the Ciggy Plug adapter is removeable and goes on or off in about 5 seconds.

[MudRunnerTD]

I just fixed a couple of odd predictive script stuff in my first post.

I just read ETs comments on the engel plugs. I have no experience with them so I will trust what ET say and I simply can't think of a time where he has led us a stray! He knows stuff!

I will say tough the Anderson plug works a treat. They are cheap and easy to work out. I have made an adapter Anderson plug to Ciggy plug if I ever want to use it elsewhere. Works for me. I don't have an Anderson plug in the GQ (must do that) so use the adapter when running the engel in the GQ.

[Smoothrun]

Before I add notes and for those who have replied, I say thankyou, but Please bare with me guys Im fairly new at forums, including replying with quotes adding pics and somehow just read all the input on this including Cuppa's and ET's which i didnt get a thread reply message for, others I did read yesterday, Not meaning to sound rude for late replies but between getting notifications whilst im at work (driving),using my secondary crappy phone whilst No1 is being repaired over next 2 weeks im limited for comms. Not to mention I sleep during the days and start work at 5pm and home 6-7am, hence this early reply now.

Cheers

[Smoothrun]

I would run it straight to the back and install your sub board in the rear. Put a fusable link under the bonnet for the wire running to the back. I have run a single 35mm2 wire to the rear as the supply as there is then no voltage drop and I can run whatever I like. Including the option to wire up an Anderson plug at the tow bar for the camper trailer charge.

Swap your fridge plug for an Anderson Plug.

I have a fridge in the back permanently. I have a second Anderson plug outlet for a second fridge when touring if I want it.
I have an Anderson plug to hook up a 1500w pure sine wave inverter in the rear too.
I have an ARB hi output compressor permanently wired.
I have running water via a 12v pump at the rear.
I have a rear work light
I have multiple led lights to the rear.
I also have multiple charging point a at the back for when at camp to run lead lights or to charge the iPad etc.

The sub board works great and there is no voltage drop.

Earth you second battery to your motor and your chassis. Earth your sub board to the chassis.

That's what I have done and works a great.

Thanks mudrunner, I did contemplate 2B&S and was actually thinking about getting Welder cable from BOC or CIG for the job, like I said im only limited in Autoelec stuff, mainly car audio gear over the years and this stuff is leaps and bounds ahead of me, so this is where ill start getting lost,

Taking into consideration that everything will be fused at the rear of the car which is what I want I was thinking about what to have under the bonnet, my thoughts were to have an isolator switch for emergency, welding, works etc, then I got to thinking, would a say 50A fuse be ok under the bonnet which is something I could keep above the rear 40A and if faults are found under 50A then the source would be found at the rear, would that be ok to do, then Id put the isolator down the back next to everything before the sub board of course. Id be interested to know how you went about it, also if you could give me any advice on a decet sub board id appreciate it.

Cheers Smooth

[Smoothrun]

The fuse blocks I used are from Jaycar and they had a decent sized stud for the power input. I simply used battery lugs crimped onto the 6 B&S and bolted them to the fuse block terminal.

49504

Ill have to head down to jaycar and have another look, either they were out of stock or i was looking in the wrong place, the ones i saw were smaller, how do those style handle the corrigations and how do the terminals hold up being exposed Sooty?

Smooth

[Smoothrun]

Do as you’ve suggested, plus add MR’s suggestion for an Anderson plug on fridge.

I’m not sure what current your compressor draws, but if it’s anywhere close to 40 amps, then putting a higher amp fuse at the battery would be worthwhile otherwise you run the possibility of blowing it if you ever run something else at the same time as the compressor.

Unless you have a very small & super efficient fridge it will most likely draw more than you suggest. Your figures look more like ‘average’ draw to me (i.e. taking into account the off cycle, & averaging total use throughout the 24 hour period & dividing by 24. I’d guess when running 3.5amps to 5 amps would be more likely. A 7.5 amp fuse should suffice. If it blows on start up, put a 10 amp one in.

Something worth considering is to use circuit breakers rather than fuses. Over time & in mobile situations like ours where vibration is part of the equation they are safer & more reliable. Lots of instances of blade fuses becoming high resistance over time & melting, with fire being a potential result. I don’t know why but this seems more common in the multi fuse blocks. Loads of people will tell you that they have used these multi fuse blocks without problem.... and they have, but I have seen & heard of plenty occasions where catastrophe or near catastrophe has occurred. (From melted fuses & wire insulation to complete loss of vehicle). Circuit breakers come in a number of ‘flavours’. I like the type that are switched, as they double as circuit protection & on/off switches, & don’t require spare fuses to be carried.

If you want to stick with fuses then this sort of ‘resettable fuse’ gives a little extra convenience. They are available in a variety of amperage values.
http://www.ebay.com.au/itm/NARVA-55730-30A-CIRCUIT-BREAKER-REPLACES-STANDARD-BLADE-FUSE-BATTERY-/221498871612?pt=Caravan_Parts_Accessories&hash=item33925c8f3c

I was thinking id only need a 5A to 10A fuse for the fridge Cuppa, appreciate you clarifying that up for me. For the record ive got an Engel mt60f rated @ 4.2A, i shoulda worked out the formula for power usage but between doin all this research and reading up on everything i need to do to my new rig ive had to lapse out on some details which i will get around too,

As far as circuit breakers go im not new to the idea of it and definitely the way id prefer to do things, but like i mentioned my experience is not ready to start playing with them yet and i dont know anyone who has, so im thinking about finding the safest most sturdiest fuse bank i can and go with that for now and ill do some homework on the breakers a little later, and thanks for the link re the resetable fuses,

One question if i may, whats the difference between a curcuit breaker and a resetable fuse, more power options or u can link 2 or 3 curcuits to one side and run those inline, might sound stupid but first thing that comes to mind if thats what they do/are for

Appreciated

Smooth

[Winnie]

Glad I read this, I had no idea the Engel plug unscrewed to reveal two pins, I have two anderson plugs here I was going to use for the fridge but I'll use those for something else and get myself an Engel surface socket.

[cgm]

Can someone post a pic or a link to the Engel plug "exposed"? Want to be clear - might have missed this in the past too.

[Winnie]

Here it is CGM
http://www.portablefridgesonline.com.au/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/e/n/engel-jcord-popup-1.jpg

[cgm]

Here it is CGM



That's cool. I'd never noticed before that you could actually screw them in.

Thanks to ET for pointing it out. Definitely another option for various things, and it can't rattle out.

[the evil twin]

That's cool. I'd never noticed before that you could actually screw them in.

Thanks to ET for pointing it out. Definitely another option for various things, and it can't rattle out.

My pleasure.

You can source the sockets for your vehicle from a few places.
Baintech have a couple of variations but are a tad expensive at $30 and up
OR
You can Google around and see what you can get... search for "posi-fit" usually finds some
OR
Narva Part number is 81132 and single outlets are around $15 to $20 on Ebay

Plugs are also available for converting other brand fridges or accessories and Narva Part number is 82109
Usually the cheapest option is Ebay (Narva or Baintech) however that is without the Ciggy Plug nose

[Cuppa]

One question if i may, whats the difference between a curcuit breaker and a resetable fuse, more power options or u can link 2 or 3 curcuits to one side and run those inline, might sound stupid but first thing that comes to mind if thats what they do/are for



A re-settable blade fuse is a small circuit breaker designed to fit into blade fuse holder. It has the advantage of not needing to carry spare fuses to replace, but compared to other circuit breakers where wire connections are usually made with a screw type connection, the re-settable fuse still has the blade type connection of fuses. It is the blades & the holders which over time can oxidise causing them to become high resistance & to get hot without the fuse blowing.

To be honest I’m not sure what a resettable fuse would do in this situation, but I’m guessing it would be more likely to break the circuit than a fuse would. I wonder if anyone else might comment to clarify?

[Cuppa]

Anyone fitting or using blade fuses could do worse than read this article.

http://caravanandmotorhomebooks.com/blade-fuse-problems/

[Smoothrun]

My pleasure.
Narva Part number is 81132 and single outlets are around $15 to $20 on Ebay

Plugs are also available for converting other brand fridges or accessories and Narva Part number is 82109
Usually the cheapest option is Ebay (Narva or Baintech) however that is without the Ciggy Plug nose

Thanks for the input ET. I actually had a look at the plug yesterday and unscrewed it and saw the pins. was not aware the pins can go directly to a socket and screw in. ill check em out in the morning after work. might even consider that type for work lights etc. ill still run an Anderson down the back for athere options.

cheers

[Smoothrun]

Anyone fitting or using blade fuses could do worse than read this article.

http://caravanandmotorhomebooks.com/blade-fuse-problems/

Appreciate you putting that up cuppa, I did Cape york in 2003 and pulled up beside a car broken down on the tele track with electrical issues, after we stopped I noticed that he'd used his fire ext under the hood and was concerned about his wiring ethic, well his words were more like sh*&, Fu@! to be more to the point, and it looked a mess because of the foam, but he was quite certain he could fix it and was not requiring any help and we carried on, so I never actually found out what had happened, I dare say it looked very similar to the pic in this read up. I also agree that we could do worse than read it.

A valuable Read for sure

Cheers