Heath Zenith Hero Jr - No HTML

From: Lawrence Walker <lgwalker_at_look.ca>
Date: Tue Mar 27 19:13:16 2001

 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

> > 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
>
>



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Received on Tue Mar 27 2001 - 19:13:16 BST