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[ray t]

Hi all

I am looking to run two 7.2v nimhs in parallel (some will disagree I know) and I would like the option to use a solar panel bankside to charge the cells whilst still in the boat.  After use I will simply remove the packs and charge them at home.

My question is, is it as simple as connecting both packs to a charging socket and then plugging the charger into the socket.  This is what I had in mind:



Any thoughts?

[pugwash]

Ray, In my humble opinion it would not be worth it.  We had a solar panel 4' X 3' on a yacht in Greece
where all the sunshine is to found and it just managed to keep to batteries topped up when we were
running a small 12v fridge when we were at anchorage, but, we couldnt run the radar, VHF or chartplotters
etc at the same time or you could see the battery voltage going down on the meter- what size of panel
could you fit on a model???

Geoff

[Prophet]

Try this for solar model boats.. might give you an idea in either direction . waste of time or take it further
http://www.members.iinet.net.au/~gveale/solar/


if your looking for charging your batterys while your out and about boating for the day, i have seen many people use huge lorry batterys and hook there batterys up to it to quick charge ( clubs day out) other options are flash chargers run of the car lighter port search online for them

[DickyD]

I think he actually said "panels at the bank side" Mr Pugwash, not on the model.

[Netleyned]

I think he means a solar panel ashore to charge the batteries when not afloat
Ray, its a no no because the solar panel would not put in any worthwhile charge
in the time it would be connected.
Either buy a 12volt input charger to use from the car or buy a couple of spare packs
Both cheaper options
IMHO I would get a couple of spare packs or if room higher capacity batteries


Yours Aye

Ned

[Shipmate60]

Although I do run battery packs in parallel I never charge in parallel.
This is fraught with problems.
And as has been stated the trickle charge that you would get would hardly be worth it.

Bob

[pugwash]

Sorry Dicky,  Brain (such as it is) didnt see what the eyes saw.

Geoff

[ray t]

Sorry guys, think I may have mislead some of you    I already have a solar panel.  It is a 13W panel which charges at around 750mA.  I also have 8 new 3800mah packs so shouldnt really need to use it but I was just wondering if I did would I be able to use the cct

[roycv]

Hi all, if my arithmetic is OK then recharging 2 x 3800mAh batteries in parallel at 750 ma. is going to take at least 12 hours.

Just think of the cost of sandwiches, coffee / drink, suntan lotion, just to stay out there that long.  Not often you get 12 hours of sunshine in one day either.

You might need a book as well as most of our lot would have gone home after 3 hours.

However I would not use that circuit configuration, first I would retain the Tamiya connectors as you have several sets of batteries, enabling an easy change, then the circuit should be built into a dpdt switch as per RC on/off with the Off side connected to a charge socket, the batteries connected to the Centre contact and the On side to a meter point to check voltage.

I have just bought some 3800 mAh batteries off the internet at 4 for £24.99 inc p&p. are these the ones you have and are they OK?

Good luck and regards Roy