DIY : Dual battery

[4ePikanini]

I have started on my dual battery box.

This is what I have in mind

I'll post up some pics as I go along. I don't have the DC-DC charger or the inverter yet but I'll start with the stuff I have.

[tsblack]

Hi Marius

I highly recommend the Redarc BCDC dc-dc charger. We've installed two of them now and they work like a charm. They don't have a 220v in, but they do autosense when the alternator is running and so don't need a turn-on relay. Small, compact, no fans and charges a calcium battery up to 15v as needed. Fully waterproof and robust, can be engine mounted.

Have to be imported from Australia unfortunately.

-Thomas

[4ePikanini]

I purchased an 800w inverter



Converts 12V to 220V. For Home appliances up to 800w output. Over & under voltage automatic cut-off. Short circuit protection. Under voltage alarm.

I might stray from my original sketch and just have a cole hersee solenoid in the engine bay as the previous owner already ran thick cables to the back, so I'll just have the alternator charge it and I'll have a port where an external 220v intelligent charger can charge it at home etc. That works out cheaper than a dc-dc charger.

The inverter is mounted on the outside of my toolbox with the wires being run inside. It is just too big to fit inside the toolbox with the battery and I didn't want to get a smaller lower wattage one.

[tonton]

Marius,

That looks like a proper one. Where did you get it, and at what price?

Anton

[4ePikanini]

Midas had it on special yesterday. R660.

it is 800watts with 1200watts peak
internal short circuit protection cut off
maximum wattage overload cut-off protection
low voltage alarm (10.5 volts)
low voltage shut down (below 10 volts) - I like this option!

It is an auto gear brand.

The usual rate is usually about R1 - R1.50 per watt so I snapped it up when I heard the price.

[tonton]

Thanks - I will go check our local branch right away...

I would like to lay wiring from the battery to the rear (Where the little lighter plug is at the back) and connect the inverter there (on independent wiring) as and when needed. I recon an anderson plug and "lekker" thick wiring (such as the wiring on your pic) will do the trick?

I would appreciate it if someone can give me the spec for wiring (say a length of 4 metres) to wire an inverter of this caliber (800watts with 1200watts peak).

Thanks,
Anton

[4ePikanini]

Jip. I'm lucky. The previous owner's existing cables are about the size of a citi golf's starter cables so I'm sorted there to charge the 2nd battery (I have checked and only get 0.1v drop over the length)

From there I cut the supplied cables for the inverter and connected them to the 2nd battery via new terminals so they are properly secured with a good connection.

I just need to figure out how to go from the inverter's supplied 2 point feed to a 3 point plug - my only gripe with the inverter because it doesn't give a standard 3 pin plug.

[4ePajero]

I assume you have a nice fuse in that + cable leading to your battery setup in the back?

[Mcnoogle]

Hi Anton,

I used to do a lot of sound in my earlier days, a 4 gauge (8mm) cable should do the trick, I used these as standard to run up to 4000w amplifiers that up to 60amps

If in doubt, you can use a 2 gauge (16mm) cable as well, but that overkill.

Cheers
Ned

[4ePikanini]

I assume you have a nice fuse in that + cable leading to your battery setup in the back?

funnily enough the previous owner neglected that part. I have disconnected the cable until I can fit a suitable fuse and the hersee solenoid.

The battery box is nearly finished though - doing very little at a time as I'm overly busy at work.