Thread: Replacing battery terminals/leads - what best to replace with?

Originally Posted by trout1105

Many DBS systems employ a Dc to DC charger to keep the auxiliary battery topped up and most of these are rated at 20a and some of them are 40a
The charge from modern alternators are at least 120a and many of them are much higher than that and this high rate of charge is only delivered to the cranking battery

I think you are using the wrong dbs! Traxide usi160 has a continuous operating rate of, well you guessed it, 160amps. It can also handle a surge of 240amps.
So if your winch is wired to your auxiliary battery, it can pull amps from both at the same time.

Originally Posted by Vern

I think you are using the wrong dbs! Traxide usi160 has a continuous operating rate of, well you guessed it, 160amps. It can also handle a surge of 240amps.
So if your winch is wired to your auxiliary battery, it can pull amps from both at the same time.

I agree, The Traxide systems will do the job But Many of the other ones wont and Not everyone has a traxide system fitted.

Originally Posted by trout1105

Many DBS systems employ a Dc to DC charger to keep the auxiliary battery topped up and most of these are rated at 20a and some of them are 40a
The charge from modern alternators are at least 120a and many of them are much higher than that and this high rate of charge is only delivered to the cranking battery with the DC to DC charger setups.
A winch can draw upwards of 400a But is usually about 180a-250a in most cases and having the Full available power from the alternator going to the battery being used to power the winch is pretty important, This isn't the case if only 20a-40a is being delivered the the auxiliary using a DC to DC charger and the winch is run from this battery.
This is why I suggest that the winch is hooked up to the main battery and Not the auxiliary

Totally understand that, but my replies are to the topic at hand too.
As far as I remember Angus's DBS is a Redarc(memory may be failing here), so I'm replying on that basis.
Redarc 80 Amp solenoid I think, which is what I also have.
So if we base our replies on that info rather than just generalised info, I'm guessing that may help Young Angus more so that just more info that he may not really require(and possibly confuse).

So with the assumption that he has a winch(going by his comment about winching) as well .. and that he's got dual yellow tops, possibly with the second in the battery tray location at the passengers front corner in the engine bay and using the Redarc SBI12(80amp) DBS:

Large 4B&S cables for minimal voltage drop and maximum current transmission. probably needs 2m, but 3 will be safer.
New terminal lugs(crimp or solder, I just reckon solder is better/stronger/more durable/easy to do without much expense) he has 80 amps going to the auxillary, and assume that he wants to protect his cranking battery as much as possible too. Having a manual over ride for the controller is handy if ever needed too(Redarc has the allowance for it, easy to install)
Connect winch to aux, leaving the main battery as a last resort.


Additional handy aux battery stuff: run a nice large (8B&S is ideal) cable to the rear, to power fridges and other stuff with minimal volt drop. Easy to do under car and bring back inside via various grommets at the back.
Connect 8B&S cable to a large fuse of some type to the aux battery for added safety.
At the rear, connect the 8B&S to another safety cutout(I used a 40amp auto cutout relay) and all other power needs come off that relay.

That's the way I've set mine up and took me a couple of hours, and very easy to do. Trim comes forward enough to do it all without the need to strip the car entirely.

On our last camping trip, I had a problem with the fridge plug(getting old now at more than 20 yo) and the metal tip fell off the body of the plug and got stuck in the power port. Obviously couldn't see this when I went to remove the plug and it shorted out.
Having the 40amp relay protected all other stuff from this rear power port to the aux battery, and once the power at the aux end of the 8B&S cable was removed, auto cutoff relay came back online and power to the powr ports was restored with the metal tip of the broken plug now removed.
I have a 4 port set up at the rear, 3 power and one volt meter and USB port combined. The volt meter/USB port died in the electrical attack, but no fried wiring or other damage upstream(USB ports and volt meters and stuff) as the relay did it's job.

Originally Posted by Morry948

I prefer these type, but they are not perfect. Gives better high current performance for started motors and winches with 10mm+ cable

Lugs/clamps/post/connectors are only as good as the surface area they make contact with. More surface area means less resistance and heat where they join ( used to work on 50v battery systems capable of a few hundred amps )

You can also use longer bolts and turn them upside down ( ie feed them from underneath ) with a nut on top over the clamp plate, then just use the bolt as a terminal post

And use wool fat ( Chemist --> baby aisle ) on the terminals to stop corrosion. Its much better than petroleum jelly.

TerminalBT11.jpg

I lined up a local auto elec this afternoon who said he'd upgrade my terminals and re-terminate all the ends going to them and generally tidy things up, all for a pretty good price, and he said he uses these exact terminals and always gets good clean reliable results with them.

I just make my own DC distribution setup

Every setup is different, just depends on what you are doing

Use easy to get bits from your local electrical wholesaler

Off road is not anything special electrically, so dont get sucked in by the hype

Fine strand big fat cable is the GO as it is more flexible, but is more $$$

DO NOT GO relays on high current cct's, they work....for a bit...then they melt...and then you are in trouble

Good old fashioned electrical link bars are perfect as you dont need any crimpers or lugs

For dual batteries and winches, get the biggest cable you can, and most importantly, get proper crimped terminations that suit the cable size

The best battery isolator is removing the terminals from the battery post

...oh...and dont forget, cable size is measured in cross sectional area, not the diameter, and bigger is always better

And...most people over think things like this

Keep it simple folks

Originally Posted by Morry948

And...most people over think things like this

Keep it simple folks

Like soldering!
As a sparky, i have never seen lugs soldered in the field!

Originally Posted by Vern

Like soldering!
As a sparky, i have never seen lugs soldered in the field!

I have....and some very ugly ones at that, mostly done by those that had NFI how to solder, and even worse, thought that soldering it would fix it...

Mind you, if you have ever had to pour molten lead in a mold to create bonded terminals for adjoining batteries in large banks... that is art...and fun