Hi, I have tried to get hold of a battery charger that will charge a 14 cell 21V pack with zero luck. Would it be difficult to make one, and if anybody has the required information would they do me a wiring diagram, or contact me by PM or email. Thanks Ray
Use one of these
http://cgi.ebay.co.uk/Universal-DC-Power-Adapter-Charger-for-Laptop-Notebook_W0QQitemZ260501308234QQcmdZViewItemQQptZUK_Computing_LaptopAccessories_Po
werSupplies?hash=item3ca716834a
Just cut the end off and use insulated croc clips, cheaper than making one.
Cheers,
Bob
Unfortunately that is not a stand alone charger, it's simply a power supply with a selectable output designed to replace a laptop adapter. With
most commercial products the charging intelligence is inside the product itself and/or the battery pack.
Charging NiMH cells properly (i.e. with reliable automatic charge termination) is surprisingly difficult. If you just want a simple constant current
charger that you manually switch off after a certain time or when the cells get warm that's rather easier.
This is a good ready made solution for a very reasonable price, but you will need a suitable power supply for it to use
from the mains. An old laptop adapter may well be suitable for this application (check voltage and current ratings though!).
14 cell and 21V?? Are you using 1.5V cells??
That strikes me as strange, most cells are 1.2V, therefore 15 cells would be 18V.
One of these could do 18V (15 cells @1.2V)
>>>charger
linky
I used to use an ansmann to do a 14 cell pack for a dive torch
Hope that helps
Sean
Mike that is ample to do the job in hand and would give exactly the same results as the original charger supplied with Ray's kit (a large chinese
made r/c car I believe).
The other charger would be better but I think if you factor in its cost and the the cost of a 12v supply to power it you could buy a brand new car
with charger.
Cheers,
Bob
quote:
Originally posted by splitrivet
Mike that is ample to do the job in hand and would give exactly the same results as the original charger supplied with Ray's kit
The chargers supplied with those type of R/C cars had no current limiting or overcharge protection, I should know I used to sell them. It would be a
doddle to make a charge limiting circuit if required.
Cheers,
Bob
Hi Guy's, well still in the dark, as the ideas so far don't seem to fit the bill. Looks like I am going to have to tell the grand kids that its beat grandad this time, now that is a first. Thanks anyway. Cheers Ray
quote:
Originally posted by Chippy
Hi Guy's, well still in the dark, as the ideas so far don't seem to fit the bill. Looks like I am going to have to tell the grand kids that its beat grandad this time, now that is a first. Thanks anyway. Cheers Ray