Wiring up compressor

[landoman]

I have an ARB compressor in a box .....but sick of pulling out the seat to get at the battery ,.......want to hard wire it up ........so questions

If the existing wire on the compressor not long enough to get to the battery and I need to extend it ,what size ? Thickness ? Amp ? Wire should I use

Want to use 50 amp Anderson plug to allow easy disconnection , would this be ok

Also do I attach the negative wire to the battery neg terminal or to the car body

The compressor has 40 amp fuse in the lead ...should this be close to the
battery ?

Many thanks

[Blknight.aus]

which variant of the defender?

generally.

you want the fuse close to the battery and you want to run both the positive and the negative back to the battery or to a major earth point such as the body earth strap or a body earth connection fitting and NOT an internal earth distribution block/junction connector itself as that can cause some issues in some circumstances with overloading the earth wiring from the block/junction connector to the body earth point.

[Toxic_Avenger]

If your compressor is in a box, and you want to keep it that way, then just install an anderson plug flush mount socket like this:
https://www.aulro.com/afvb/

You could then use it for multiple accessories.

As for extinding the wires, just use the same gauge wire, it should be OK as long as you are not extending it another 5m. Fuses as close as practical to the battery is best.

[landoman]

Thanks chaps .....it's a new model 2016 ......

Where would I look for the body earth strap ?

That plug looks good where could I source one ....

[Toxic_Avenger]

Earth strap is on the inside of the chassis rail directly below the battery box.
The anderson plug flush socket is made by trailer vision and can be sourced fairly easily on ebay (search flush mount anderson). About 25 clams shipped.

I saw someones install where they mounted the flush mount socket on the top of the battery box beside the passenger seat. It's an ideal location if you don't mind drilling the holes in your new ride. Spec it up with some fatter cables (16-25mm2 cross sectional area) and you dcould make it a jump start socket.

[landoman]

Earth strap is on the inside of the chassis rail directly below the battery box.
The anderson plug flush socket is made by trailer vision and can be sourced fairly easily on ebay (search flush mount anderson). About 25 clams shipped.

I saw someones install where they mounted the flush mount socket on the top of the battery box beside the passenger seat. It's an ideal location if you don't mind drilling the holes in your new ride. Spec it up with some fatter cables (16-25mm2 cross sectional area) and you dcould make it a jump start socket.

Great ....thanks for that

[austastar]

Hi.,
The earth strap on mine goes to the gearbox, so I ran a wire back up to a seat rail mounting bolt in the battery bix.
On mine the earth strap connection to the battery is not suitable to get another wire on to it.

Cheers

Sent from my GT-N5110 using AULRO mobile app

[weeds]

I wouldn't be jump starting using a 50a Anderson......you could probably get away with it but it's above its capacity.

If you running a positive to the battery than I would also run the negative to the battery......I length of twin core instead of separating the cables.

[Toxic_Avenger]

Yeah you're right, the Anderson SB 50 is probably a little underspecced.
Would depend on the size of the engine, wiring used, type of starter motor etc.
The 50A rating is continuous, so intermittant use at higher amperages is permissible, but to what extent is the real question.

There is some good info on their website SB? 50, SB50, Small Anderson Plug, Anderson Power Products (http://www.andersonpower.com/us/en/products/sb-sb-boots/sb-50.aspx)

[landoman]

I wouldn't be jump starting using a 50a Anderson......you could probably get away with it but it's above its capacity.

If you running a positive to the battery than I would also run the negative to the battery......I length of twin core instead of separating the cables.



The negative terminal connection on my primary battery has this ridiculous cone shaped nut that makes getting connectors in to it near impossible

I found what I think is the earth strap ....a nut on the inside of the chassis under the battery box with what looks like one wire not too thick attached to it so will probably use this for the negative wire .............is there any complications I might get from this approach ?

[austastar]

The negative terminal connection on my primary battery has this ridiculous cone shaped nut that makes getting connectors in to it near impossible


Hi,
That is why I brought a wire back to the battery box from the other end of that earth wire which is bolted on to the gearbox.

Cheers

Sent from my GT-N5110 using AULRO mobile app

[86mud]

Here is my set up. I have two compressors under the drivers seat permanently mounted and both connected directly to the battery under the passenger seat (this is my starting battery). First off is the ARB compressor that runs my lockers, then there is the big twin ARB Compressor which is linked to two tanks under the floor.

The big twin ARB compressor has a huge fuse holder which required me to cut a rather large hole in the battery box.

I also added breathers to the air compressors which I have sitting between the cab and the ute canopy.

[landoman]

Hi,
That is why I brought a wire back to the battery box from the other end of that earth wire which is bolted on to the gearbox.

Cheers

Sent from my GT-N5110 using AULRO mobile app

Thanks for that .....is there any reason I could not just attach the black negative wire on to the same bolt on the chassis where that wire is .......

[austastar]

Thanks for that .....is there any reason I could not just attach the black negative wire on to the same bolt on the chassis where that wire is .......

Hi,
None at all. I brought the wire up to give me access to a good earth
for future use.

Cheers

Sent from my GT-N5110 using AULRO mobile app

[landoman]

Hi,
None at all. I brought the wire up to give me access to a good earth
for future use.

Cheers

Sent from my GT-N5110 using AULRO mobile app

Great ...thanks for that

[Toxic_Avenger]

The big twin ARB compressor has a huge fuse holder which required me to cut a rather large hole in the battery box.
http://www.aulro.com/afvb/attachments/90-110-130-defender-county/114549d1475026251-wiring-up-compressor-p1011242.jpg



I avoided this by cutting the fuses out, and attaching lugs.
I use a MIDI fuse and fuse holder instead of the factory maxi fuse (Slimmer design, same amperage)

[landoman]

If your compressor is in a box, and you want to keep it that way, then just install an anderson plug flush mount socket like this:
https://www.autoelec.com.au/ssl/cms_autoelec/assets/TV333820-50_3.JPG

You could then use it for multiple accessories.

As for extinding the wires, just use the same gauge wire, it should be OK as long as you are not extending it another 5m. Fuses as close as practical to the battery is best.

Fitted one of these at the rear of my truck to plug in my portable compressor to
.......nice bit of kit
Question .....given this plug in the back is primarily to drive my compressor is it better to hook up its wiring to the main cranking battery ....or to my second battery ....which I run my fridge from

Thanks again

[Toxic_Avenger]

I wired my compressor to the second battery.
Reason being that the battery controller should prevent the cranking battery fom running flat, so all non critical electrical loads I've put on the 2nd battery.
Best make that decision yourself, as it really depends on what else you are planning to run off that socket, and how much you plan to use the compressor.

[weeds]

Given the amps compressors pull I always run the engine when using the compressor.....

[landoman]

I wired my compressor to the second battery.
Reason being that the battery controller should prevent the cranking battery fom running flat, so all non critical electrical loads I've put on the 2nd battery.
Best make that decision yourself, as it really depends on what else you are planning to run off that socket, and how much you plan to use the compressor.

Thanks for that ......will probably hook to second battery then ....just to be safe
And run engine while I air up .......mostly use the compressor for all 4 wheels after sand ....or on long trips as required ......my ARB compressor in a box has a "no load" of 13 amps and " load " 23 amps ...........not sure how to translate that into how much battery drawdown it would use on airing up 4 tyres ........my second battery is an Opima yellow top ....? 50 amp hours ?

[Toxic_Avenger]

So the compressor will draw 13A at no load (imagine having it turned on, and flowing but not connected to a tyre). Once you start inflating a tyre, it will put additional load on the compressor and it will need to draw more current.

As for the Ah reating of the battery, mostly it's rated at 20 hrs, so a 50Ah battery will be able to supple 50/20= 2.5A per hour for 20hrs until discharge.

Someone might have a better explanation, but that's the short story.
There's also a number of tools out there to help calculate the Ah requirements of a battery bank given a known current draw. When you start adding solar input and everything else back in, then things change again... It's a bit of a black art ;)