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<DIV>I heard a good one yesterday that applies directly to this stuff:</DIV>
<DIV> </DIV>
<DIV><STRONG><FONT size=3>" I am too poor to buy cheap"</FONT></STRONG></DIV>
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<DIV>Goes for servos too</DIV>
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<DIV>regards</DIV>
<DIV>The Frugal Pattern Gourmet</DIV>
<DIV> </DIV>
<DIV>In a message dated 3/9/2006 8:29:43 PM Eastern Standard Time,
d.pappas@kodeos.com writes:</DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>Hi
Jim,<BR>It meets my "spec", if you will call it that: even if it is made up of
two boxes.<BR>Function first! The price is cheap compared to toasted lithium
...<BR><BR>Thanks for the confirming info,<BR>Dean<BR><BR>
-----Original Message----- <BR> From:
nsrca-discussion-bounces@lists.nsrca.org on behalf of J.Oddino <BR>
Sent: Thu 3/9/2006 7:35 PM <BR> To: NSRCA Mailing List
<BR> Cc: <BR> Subject: Re: [NSRCA-discussion] Big
LiPo pack charging<BR> <BR> <BR><BR>
Dean et all,<BR> I've been playing with the Thunder Power
TP-1010C charger and TP-210V<BR> balancer. I guess they
fall into the category of having a fancy<BR> communications
link. Some of the features:<BR> 1) If any cell in the pack
gets to 4.235V charging is interrupted.<BR> 2) During the
constant current charge phase, the charge rate is reduced to<BR>
300ma if the unbalance exceeds .12V. During the constant voltage phase
it<BR> will be reduced to 300 mA if the unbalance is greater than
.06 volts. I<BR> believe the bleed current can go up to 450
mA so it can more than overcome<BR> the charge current in these
modes.<BR> 3) If the unbalance is greater than .2 volts the
charge will be interrupted<BR> and you get a message that tells
you to balance before charging.<BR> 4) If the charger cell count
doesn't match the balancer data you get an<BR> error
message.<BR> I believe this meets your requirements except that
it is a two box system.<BR> <BR> What I like about
it is you can read the voltage of each cell (up to ten<BR> cells)
to one millivolt so you always know what you've got. I plan to<BR>
charge two 5s4p packs in series and I can't see why I shouldn't be able
to<BR> keep all the cells balanced even if I don't charge to 100%
between flights.<BR> <BR> It is pricey but if it
helps keep those expensive big packs alive it is<BR> worth
it. Plus I love the peace of mind I get when I have the data
that<BR> tells me everything is A okay.<BR> Jim
O<BR> <BR> ----- Original Message -----<BR>
From: "Dean Pappas" <d.pappas@kodeos.com><BR> To:
<chad@f3acanada.org>; "NSRCA Mailing List"<BR>
<nsrca-discussion@lists.nsrca.org><BR> Sent: Tuesday, March
07, 2006 7:59 AM<BR> Subject: Re: [NSRCA-discussion] Big LiPo
pack charging<BR> <BR> <BR> > Hi
All,<BR> > I hear discussions about this charger versus that,
and while I am not<BR> going to try and sell my preference, I
think I<BR> > should tell you what a proper charger, for our
purposes, should do.<BR> ><BR> > I really
think the important thing to remember, here, is that a real<BR>
balancing charger will always be better than a charger plus an
add-on<BR> balancer.<BR> > Why? The add on
balancer and charger combo will do its job, perfectly<BR> well:
until there is a problem with a battery pack.<BR> >
Unfortunately, this is where the safety hazard happens (not to mention
the<BR> premature aging of expensive battery cells).<BR>
><BR> > When there is a problem, and the imbalance
between cells is not slight, or<BR> some cells have appreciably
different capacities than others due to age,<BR> > the
controlled bypass current around the higher voltage cells may not be<BR>
high enough to keep things balanced.<BR> > That's how
balancers work, they put a current "leak" across the higher<BR>
voltage cells;<BR> > during charging this leak shunts some of
the charging current around the<BR> higher voltage cells, until
the lower voltage cells catch-up.<BR> ><BR> >
For things to really work properly, the balancer part of the works
needs<BR> to be able to throttle-back the charger
current,<BR> > to something equal to or less than the maximum
leak current, at any stage<BR> of the charge, if the imbalance
isn't getting better.<BR> > That really requires a one-piece
balancing charger, or some sort of fancy<BR> communication
between the charger and balancer.<BR> ><BR> >
Right now, very few companies make a real balancing charger, but
this<BR> can't stay the same for long.<BR> > It
has also been suggested that with a true balancing charger, that
never<BR> charges too fast to maintain balance,<BR>
> that 2C and 3C charges are possible, with the high C discharge packs
we<BR> find necessary, in Pattern.<BR>
><BR> > later, friends,<BR> ><BR>
><BR> > Dean Pappas<BR> > Sr. Design
Engineer<BR> > Kodeos Communications<BR> > 111
Corporate Blvd.<BR> > South Plainfield, N.J. 07080<BR>
> (908) 222-7817 phone<BR> > (908) 222-2392
fax<BR> > d.pappas@kodeos.com</FONT></BLOCKQUOTE></DIV>
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