North Australian FISH FINDER forums

Ok, I'm thinking AGM's for my new 80lb Minn Kota, I think i'll part with the extra cash seeing they be locked down in the cast deck. I've been quoted 320-350 in most places around darwin for a 120ah.

My question is though, why do you need to have a 24v charger? Wouldn't a 12v charger with dual capability be just as good? I know the system becomes 24v once you're in series but each battery is still only 12v? Hopefully one of you tech's on here can offer some advice?

24 volt charger gives good even volts between the 2 batterys as opposed to charging one then the other with a 12 volt.. so ive been told anyway, it makes sence tho...

Hi Mac10

You can charge the batteries in parallel with a 12v charger. Bit of mucking around changing wiring from series to parallel connection for each charging session. Might be better to take out of boat to charge perhaps?

I'm guessing you have a 12v charger already?

The charging current in each one will be half whatever the charger would deliver into 1. Take longer to charge. Lot of weight there.

Good luck.

Thanks guys, I'm planing on setting up the new boat to be as user friendly as possible. Batteries will be set down low in the hull so by the sounds of it i'm better off getting a new 24v charger to save changing it all the time. Can I set up a permanent lead on something like an anderson plug so I can plug the charger straight in? Or I guess better yet use the same anderson plug that connects power to the Minn Kota?
Cheers
Chris.

Spend the money on ctec 24v put a Anderson plug on it. The anderson plugs make real easy to charge both batts at the same time. I can charge my 2x 120 amp batts in less then 12 hrs from flat. I have a cheaper one and it wasn't up to the task that's was I brought the new one.

Running any sort of battery down to flat will only halve their life. Deep cycle batteries are best let run down to 50%, normal everyday car type acid only like no more than 10-20% taken out of them. AGM batteries are best suited to running devices such as the Minn Kota. Battery World has 232ah 12V Deep cycle batteries suited to golf carts for $250 if you ask for a deal. These will do the job easily and not run down too much and they are not much bigger than a normal car battery.

I thought you could run Agm batts flat that's my understanding.

Chris

You can use an anderson plug set up as you describe with a 24v 3 stage charger suitable for deep cycle batteries.

Be very wary of "sealed maintenance free" batteries unless they are VRLA or gel types.

Ended up getting 2x120ah Agm's from I&O for $620. Happy with that.

Next question, will 6mm cable be sufficient to connect both batteries in series or am I better of going heavier for this.

Hi Mac10
It depends on how long the cable run is between the batteries and the electric motor. When it comes to cables bigger is better as there is less losses. 16mm should be sufficient. Make sure you have a fuse or a circuit breaker in series as well because those batteries will supply a lot of current in fault condition.

I am going for AGM batteries for my 80lb Minn Kota. Give George a call at NT Unique in Yarrawonga, he knows his stuff and I am sure he can help you out. Awesome boat builder and bl..dy great bloke.

I just set my new boat up with a 55lb leccy. Got all my gear of ebay for it.
100amp/hr - 800CC AGM for $220 including freight. Good warranty too.
CTEK 10amp 8 Stage charger for $210. This has the comfort connect so you leave the leads attached to the battery and when you get home you plug the charger straight in. Same, same but diffrent to the anderson plug. You can also by a bunch of other kit that plugs into it aswell.
All my 6B&S cable and anderson plugs off there as well. (The recommended thickness for your Leccy).

Don't forget a 50amp fuse as close to the battery as possible.

IMHO if you don't mind a few days wait you can save yourself a fair bit of cash by shopping on ebay.