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irondoc
6th July 2011, 07:58 AM
hi guys

there are a few posts on here about never connecting anything up to the negative battery post on Discoverys as there are electronic "bits" that monitor currents, etc on the negative side of the battery. A body earth stud should be used instead.

my question is whether this applies to only 3.0 D4s, as on my 2.7 D4, there is heavy duty cable connecting the negative battery post to a body earth stud, but nothing in between them except the cable, and no monitoring bits sttached

cheers
lucas

sniegy
6th July 2011, 07:21 PM
Again never directly connect to the negative terminal as they use a compression crimp to tighten the battery terminal.
Use only the earth studs located in front of the factory battery box.

Cheers

drivesafe
7th July 2011, 05:37 AM
Again never directly connect to the negative terminal as they use a compression crimp to tighten the battery terminal.
Use only the earth studs located in front of the factory battery box.

Cheers

And this type of negative battery terminal ( compression clamp ) is used on the D3, D4 and RRS.

101RRS
7th July 2011, 08:56 AM
Again never directly connect to the negative terminal as they use a compression crimp to tighten the battery terminal.
Use only the earth studs located in front of the factory battery box.

Cheers

Is there the equivalent +ive terminal to take power from.

Garry

drivesafe
7th July 2011, 09:04 AM
Hi Garry and not sure what you mean but there is no problem sourcing positive from the cranking battery’s positive terminal.

Like any positive circuit, just make sure that what ever is connected to the battery’s positive terminal, that the circuit has the appropriate circuit protection, IE., a fuse or circuit breaker of the correct size for the circuit it is intended to protect.

101RRS
7th July 2011, 09:13 AM
Again never directly connect to the negative terminal as they use a compression crimp to tighten the battery terminal.
Cheers


Hi Garry and not sure what you mean

Sniegy indicated not to use the negative terminal as they use a compression crimp to tighten the battery terminal (I also appreciate there are other electronic issues).

The +ive terminal also uses a compression crimp.

drivesafe
7th July 2011, 09:45 AM
The +ive terminal also uses a compression crimp.

Yes but thankfully, LR made the clap with a pre tapped 8mm hole that makes connecting to the positive terminal a breeze.

https://www.aulro.com/afvb/images/imported/2011/07/1232.jpg

https://www.aulro.com/afvb/images/imported/2011/07/1233.jpg


https://www.aulro.com/afvb/images/imported/2011/07/1234.jpg

bbyer
7th July 2011, 09:51 AM
Sniegy indicated not to use the negative terminal as they use a compression crimp to tighten the battery terminal (I also appreciate there are other electronic issues).

The +ive terminal also uses a compression crimp.

You are correct, but per the picture below, within the postive terminal there is also a second metric threaded hole that you can screw in a bolt, (8mm?), and use as a connection point. Note that this jpg is from my LHD but RHD is similar, except that the main factory starting battery on the left side.

In my picture below, while not visible, the fuse is connected right off the bolt and tucked into the space between the case and the battery. The conductor to whatever is then connected downstream of the fuse.
https://www.aulro.com/afvb/images/imported/2011/07/1231.jpg

Graeme
7th July 2011, 12:29 PM
the fuse is connected right off the bolt and tucked into the space between the case and the battery. The conductor to whatever is then connected downstream of the fuse.
The reason for this is often not realised. The fuse or cirucit breaker must be close to the power source so as to protect the cable downstream. Its no good having the fuse on the other end because if the insulation rubs through and shorts to earth, the fuse can't prevent a fire.

I've just run a 50A cable across to a small fuse box in the aux battery spot, via a 30A CB right near the main battery.