Thread: Dual Battery System - Disco Series 2A

Hi KEV0044, can you tell us how you intend to use the auxiliary battery.
EG. 1 weekend a month to run a fridge or on a long trip and powering fridge, lights, laptop and so on.
Also do you have an idea where you intend fitting the battery, under the bonnet or in the rear luggage area, in a trailer or caravan although I get the impression that you are installing it in the Disco.
Cheers.

Drivesafe, what is the brand name of your battery controllers?

Ron

Originally posted by p38arover
Drivesafe, what is the brand name of your battery controllers?

Ron

http://www.traxide.com.au/

Thanks LRHybrid100, I was just going to give KEV0044 some ideas without mentioning my gear but thanks anyway.
By the way the site is a mess as I have not had time to update it.
Cheers.

Originally posted by drivesafe
Thanks LRHybrid100, I was just going to give KEV0044 some ideas without mentioning my gear but thanks anyway.
By the way the site is a mess as I have not had time to update it.
Cheers.

oops Sorry!!!

I do know you are not on this site for self promotion, however if some of us have products that could be of use to other members, I will quite happy
to recall their owners [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img]

Once the RR is back together I will be ordering one of your SC40's

LRH

...

Hi KEV0044, now the following is just a suggested set up and if anyone has other suggestions please jump in.

The battery cradle from either supplier will work but after fitting the cradle, place the battery in the cradle and then work out how make and fit a thin sheet of stainless steel so it will sit between the battery and the engine so that the radiated heat from the engine is reflected away from the battery. Because of the location of the second battery at the rear of the engine bay in series II Discos, I strongly recommend that you make this shield to help lengthen the operating life of your auxiliary battery.

Next, the battery. Because of space limitations, my personal choice would be a Deep Cycle battery because you get the most current capacity for a given area ( does that make sense? ).

For connecting the two batteries together I would obviously recommend using a good functional battery management system because there are a number of advantages, the most important of which is that they don’t forget and secondly because I make a buck. [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img]

Look if your happy and comfortable with the marine switch, stick with it.

With the main battery being mounted at the front and on the opposite side to the auxiliary battery, you will need to run some good size cable between the two batteries so that the Auxiliary battery will be charged as quickly as possible. I would recommend at least 8 B&S ( thats about 8 mm square ).

I can not stress this next point stongly enough, run both a positive and a negative wire. DO NOT USE THE VEHICLE BODY AS THE EARTH RETURN, you are just begging for trouble if you just earth the second battery to the body.

With the Disco as with any vehicle, run the cable from the main battery down the side of the engine bay and than across the back of the engine bay, to the other battery, don’t run the cable across the front of the vehicle, no matter how easy it may look, it is far safer to keep the cable away from the front.

All accessories running of the auxiliary battery should be connected to the battery via fuses.

Cheers and I hope this is of some help.

Originally posted by drivesafe
I would recommend at least 8 B&S ( thats about 8 mm square ).

I can not stress this next point stongly enough, run both a positive and a negative wire. DO NOT USE THE VEHICLE BODY AS THE EARTH RETURN, you are just begging for trouble if you just earth the second battery to the body.

8mm square? That's 64 square mm. Or do you mean 8 sq mm? That's about 3.2mm dia wire.

Re the second point, is that just to ensure that both batteries have a common ground and therefore the same potential - which I assume would be important for correct operation of the battery controller? Or are there other reasons?

I may be an electronics technician by trade but my experience/knowledge in this field is not much better than most others on the forum.

I notice that my recently purchased County, which has dual batteries configured via a Sure Power 702 battery isolator, has both negative leads tied together. The 702 is one of the old style diode isolators which i'm not that keen on owing to the voltage drop across the diodes. I haven't investigated whether the County alternator can use remote battery voltage sensing to compensate.

Ron