Battery Charger V/Ah - Page 7

 


That IS somewhat of a stretch but not totally impossible.
The max. current output shown is at the rated voltage.  So, for instance, a
device rated at 1.5A, 12V should supply 12V up to the rated current load of
1.5A (or somewhere close).  If you continue to increase the load, the
amperage may increase beyond 1.5A......as the supplied voltage drops below
12V.

 
It would be a strange power supply that allowed that. Although it might be
possible with different tappings on a transformer.

--
*If at first you don't succeed, try management *

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

 


True that a "real" power supply shouldn't work like that but I believe most
of what he was talking about were simple transformers, with or without
diodes for rectification.

A simple transformer is capable of supplying only so much power and P=IxE so
as the current goes up, the voltage goes down.  That's also why the output
voltage reads higher than the "rating" when it is open (supplying NO
current).

 


If you put the ammeter straight across it, shorting the output of the
charger, it would not surprise me at all if it managed 4-6A, obviously this
is not a useful measurement and it wouldn't take long for it to overheat
though.

 James Sweet wrote:

I think that's the point.  The OP didn't specify under what conditions
he did his measurements.  The ratings on any piece of equipment are only
valid under the conditions specified.  IOW, 1 amp @ 12 volts, 'might'
supply 4 amps, but perhaps not at 12 volts...and probably not for long!

My impression is that the OP is not very technically competent and that
he is being 'penny wise and pound foolish'...buying a very expensive
battery and trying to cheap-out on the charger.

If he had the chops to analyze his situation, he could probably build a
charger which would be relatively inexpensive and safe; but he hasn't
shown that capacity.

jak