Re: Charging/Amp question

["Joe Smalley" <joes@worldfront.com>]

When I was in school, the teacher gave extra credit for good explanations on
story problems. I always went for getting those extra points.

I did not include the power factor in the explanation since the power factor
is so high on a PFC-20 at full throttle. If you use something other than a
PFC-20, the power factor needs to be considered.

By the way, the charger is 95% efficient when operating from 240 volts into
a battery pack over 150 volts. I have been meaning to put that information
on the website but have not gotten it into a presentable format for
publication.

Joe Smalley
Rural Kitsap County WA
Fiesta 48 volts
NEDRA 48 volt street conversion record holder
joes@worldfront.com

----- Original Message -----
From: "Tony McCormick" <tony@notebene.net>
To: <ev@listproc.sjsu.edu>
Sent: Friday, May 31, 2002 9:03 PM
Subject: Re: Charging/Amp question


It will take me a while to absorb all that, but it looks pretty complete.
:-)
--Tony

-------Original Message-------

From: ev@listproc.sjsu.edu
Date: Friday, May 31, 2002 08:50:09 PM
To: ev@listproc.sjsu.edu
Subject: Re: Charging/Amp question

The calculations look like this:

Assuming your pack is at rated voltage during charge (not likely but we have
to assuming missing information)

Output watts = 102 x 19.7 = 2009 watts

Assuming 90 % efficiency and 20 watts of house power to run the fans and
lights.

Input watts = 2009 / .9 +20 = 2252 watts

Assuming 120 VAC open circuit and a half ohm of wire between you and the
utility.

Input amps = 2252 / 110 = 20.29 amps
--------------------------------------------------------
If we assume the pack is at acceptance voltage of 7.2 volts per 6 volt
monoblock then the numbers look like

Output watts = 122.4 x 19.7 = 2374 watts

Input watts = 2374 / .9 +20 = 2658 watts

Input amps = 2658 / 110 = 23.98 amps
-----------------------------------------------------------

Does this answer your question?

Joe Smalley
Rural Kitsap County WA
Fiesta 48 volts
NEDRA 48 volt street conversion record holder
joes@worldfront.com



----- Original Message -----
From: "Tony McCormick" <tony@notebene.net>
To: <ev@listproc.sjsu.edu>
Sent: Friday, May 31, 2002 8:27 PM
Subject: Re: Charging/Amp question


OK, so I feeding off a 120 VAC and my pack is 102 Volts, what does that
mean?
--Tony

-------Original Message-------

From: ev@listproc.sjsu.edu
Date: Friday, May 31, 2002 10:04:18 AM
To: ev@listproc.sjsu.edu
Subject: Re: Charging/Amp question

Tony McCormick wrote:
>
> I'm curious, I have a PFC20 charger and I was wondering: if my emeter
> reads 19.7 amps, I assume that means going into the battery pack, what's
it
> pulling from the AC side?
>
> - Tony
> ---------------------------------------------------------------
> My Web: http://www.notebene.net/ - EV Web: http://www.oeva.org/
> ---------------------------------------------------------------
> "Nobody made a greater mistake than he who did nothing because
> he could do only a little" - Edmund Burke



.