wrote in message
...
On Fri, 13 Nov 2015 08:25:49 -0500, Micky
wrote:
On Fri, 13 Nov 2015 03:41:20 -0600, wrote:
On Fri, 13 Nov 2015 00:48:52 -0500, Micky
wrote:
I need a DC power supply, bigger than what I've got. Any reason why I
can't connect two automobile battery chargers in parallel to suply the
same vehicle?
I've used two battery chargers at the same time on cars many times.
Never had a problem. Of course I'm talking about two small chargers.
Like a 6 AMP and a 10 AMP. I would not connect two 30 or 50 Amp chargers
together. I'm just charging at a rate of 16 AMPS, which charges the
battery faster than the individual chargers. Since you can buy a 30 or
50 A charger, 16 A is still minimal compared to the bigger chargers.
Just sharing my experience, not guaranteeing you can do it safely. But
like i said, I've never had any problems doing it.
Good enough. Thanks. (Though I've written down your email address
and my estate will be suing you if this proves fatal.)
It wont be fatal for you, it's only 12volts. But it could damage a
charger or battery, although I have never had that happen. My chargers
are old, so they dont have all the circuitry that some new ones have.
It's just a transformer, some diodes, and a reset to shut it down in the
event of a direct short. Very simple, and I have fixed several of them
over the years. Usually it's a bad diode or two, or that reset device
fails. I did have one burn the transformer out, after it got rained on.
I learned that the hard way! I always cover them now if they are in use
outdoors.
Somewhere I've got an ancient charger that the Halfords store used to sell -
the metal case is the only original part.
The rectifier was replaced with one from a motorcycle and the transformer
with one from a Philips black & white portable. The cheap & nasty plastic
moving iron current meter was replaced by an Admiralty bulkhead mounting
instrument.
A resistor was added before the rectifier to limit the current because a TV
PSU transformer doesn't have a charger transformer impedance characteristic.
A couple of big film capacitors were added to make the rectifier voltage
doubling (for some strange reason it actually gets up to about 42V with no
load!). Which works rather well for saving sulphated batteries. Later I
added a big fat electrolytic for zapping whiskered nickel cells.