27 Mar
2001
27 Mar
'01
11:13 a.m.
I have a couple of old 675W Tripp Lite backup systems with spike and surge
suppression, one of which I am using now in my multi-puter set-up. It takes
the 120v residential supply and charges up a lead-acid automobile type 12v
battery and then converts it back to 120v feeding 4 plugs. The cables on one are even
the post clamp type. I've often thought that I could likely wire it into an automotive
system for using household appliances or computers in a van for travelling.
I've been amazed at how long it still outputs during a blackout.
I believe they were originally used in an office environment. Would these
be equivalent to what you call a "high-class" charger ? I've never put a
scope across the
outputs and of course the output is further smoothed by the CPSU on the puters.
larry
Reply to:
lgwalker(a)look.ca
I was amazed
to find a local classified ad for a Hero Jr in the Saturday
morning paper and soon after I was owner of a very clean Robot for a few
dollars (about time I had that sort of luck). Unused for many years but just
Ooohh _very_ nice!!!!
The old battery will not take a charge using my
car [translation - auto]
battery "trickle" charger, so I'll have to wait 'till next week to buy
a new
12V 3.5A sealed lead/acid battery - that's how this Australian model was
In general it's a bad idea to charge sealed lead acid batteries from the
average (crude) car battery charge. Sealed lead acid batteries need to be
charged from a constant voltage source of the right voltage.
powered - not like the 6V batteries described on
the web pages for the Hero
Jr. And I don't have a 12V PSU to power it up with in the meantime. Am I
using an appropriate re-charging device? And could I use the trickle charger
itself as the PSU for testing? A multimeter reads about 13V across the
terminals when it is powered up, but with my minimal electrical knowledge I
do not dare try something that could be fatal to the Hero.
I wouldn't do it. Most car battery chargers (at least in the UK) are
little more than a transformer, a bridge rectifier, and maybe a
moving-iron ammeter. No smoothing, and certainly no regulation. After
all, for the intended use (charging 'wet' lead acid batteries), that's
all you need.
That's not the sort of supply I'd apply to electronic devices.
Of course you might have a high-class battery charger that outputs
something approximating to smooth DC, but I've yet to see one.
12V PSUs are not that hard to find. I believe the amateur radio or CB
crowd use them for running mobile (car type) rigs at home. So you might
be able to get one that was designed for that sort of use. It may well
claim to be 13.8V which, IMHO, would be fine for this application
-tony