Re: denali charger specs question

[Rich Rudman <rmanzan@tscnet.com>]

Roger Stockton wrote:
> 
> > -----Original Message-----
> > From: Sam Uzi [mailto:samuzi@kcd.com]
> > Sent: May 31, 2002 3:39 PM
> > To: evug list
> > Subject: denali charger specs question
> 
> > Denali uses Hawkers, and they are claiming that their
> > proprietary 1.2kW charger can charge the battery (from 110v
> > outlet) to 90% in 20 minutes, and to 100% in 30 minutes
> > without harming the battery
> >
> > is this realistic?  seems too good to be true
> 
> Assuming their 36V pack is a set of 13Ah Hawkers, the 90% in 20min part
> could certainly be true: 30A for 20min is 10Ah.  100% in 30min without
> harming the batteries is a bit more questionable, but might be doable.
> 
> My concern would be that there is real risk of venting one of the
> batteries when recharging them at very nearly C/1 in a series string
> unless the charger monitors the terminal voltage of each module rather
> than just the total.
> 
> I see no heat sinks on their artist's concept of the not-yet-produced
> charger and even if it achieves ~90% efficiency, I would be quite
> surprised if they can sustain this output for much longer than 30min in
> a <6lb package without it getting extremely hot.  Wonder if there is a
> reason for only a 6month warranty?
> 
> The line I get a kick out of on their page is the statement "We have
> pushed the mobile charger power envelope for over 4 years now...", yet
> they have no picture of an actual charger product of their own and offer
> a rather ordinary looking 22A 36V Schauer charger until such time as
> their Downloader is available.
> 
> Cheers,
> 
> Roger.

HUmm charger folks not delivering the goods.. 
	I am doing the final output QC on #32..... it's making 20 amps of 170
VDC. 
Just about what it's supposed to.

There are a lot of charger folks that claim stuff that is really hard to
do. A 30 amp switcher 120 VAC to 42 VDC, should be doable. at %90 they
are going to need PFC of some sort. Also doable. But spendy.
doing a Transformer, and then a switcher would be ok.
	30 amps of 42 volts is 1260 watts delivered.  In a 6 lbs package.... My
Bs detector is not Redlined but it's getting close. at %90 that's 126
watts of waste heat. That's a noticable warm breeze. It's gotta have
fans, and pretty noticeable ones. 

Downloader.... down loading watts, Nice concept. 
What's my stuff Block mover, Page or entire partition mover....
	Pushing the envelope.... Ummm that's Joe and I. We now have flashing
BLUE leds.... 1.5 Kwhr is back where it belongs... in the YTs.

God, Joe has the PFC50 in his hands tonight... Don't break it Joe!!!!
please.
Just make it quite, and solid as a rock.
Madman