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That would be a great way for Iota to set them up at the factory.
The device would be useful for many more applications, including Mick's
(in the link below). <br><br>
Or, if the charger came with an option with a more durable, user
accessible potentiometer, it would be a great tool. The way it is
now would be better for on grid applications where user tampering could
damage batteries. <br><br>
At 12:55 PM 10/26/2012, you wrote:<br>
<blockquote type=cite class=cite cite="">Hi Drake,<br><br>
Good find. We always adjust the Iota's for different types of batteries.
Since this one is only used for back up purposes with a generator, you
can leave the jumper in and always run at 15.7 volts. Once the voltage
reaches that point, you will be +/-90% charged. This will not harm a
flooded battery. <br><br>
If the converter is used long term with shore power, I would recommend
that you install a resistor where you soldered the leads together to drop
the voltage back to about 14.2vdc to preserve battery life. Also add a
switch in parallel with the resistor and you will have the ability to
select 14.2, 14.8 (jumper in) or 15.7 volts.<br><br>
Larry Crutcher<br>
Starlight Solar Power Systems<br>
<dl>
<dd>-------- Original Message --------<br>
<dd>Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger<br>
<dd>recommendations?<br>
<dd>From: Drake
<<a href="mailto:drake.chamberlin@redwoodalliance.org">
drake.chamberlin@redwoodalliance.org</a>><br>
<dd>Date: Fri, October 26, 2012 6:23 am<br>
<dd>To: RE-wrenches
<<a href="mailto:re-wrenches@lists.re-wrenches.org">
re-wrenches@lists.re-wrenches.org</a>><br><br>
<dd>Through a strange set of circumstances, I found a way to equalize
batteries with an Iota charger. <br><br>
<dd>My DLS 45 was borrowed on a couple of occasions. I made the
mistake of telling the borrowers how to adjust the voltage through the
potentiometer. Predictably, when I needed the unit, the pot had
been ruined. Calling Iota, they said there was no fix. The pot was
soldered to the board. <br>
<br>
<dd>The way the device works is that lowering the pot resistance
increases the output voltage. My solution was to cut the pot out of
the circuit board and solder the leads together. Now with the quick
charge plug out, it holds at 15.2 to 15.4 volts. The the quick
charge plug in, it runs at around 15.7 volts. I equalized a pair of
T-105s yesterday without the quick charge plug. It worked like a
charm.<br><br>
<dd>This is much more useful for my needs than the factory
configuration. My uses are emergency charges from generators, often
in cold weather, and equalization charges. The operation of
removing the pot was tricky for me, but someone more used to working with
electronic circuit boards might not find it too difficult. <br><br>
<br>
<dd>At 01:27 PM 10/15/2012, you wrote:<br>
<blockquote type=cite class=cite cite="">
<dd>Hi, Mechanix~<br><br>
<dd>Bill Dorsett polled the group about recommended battery chargers for
connection to a generator. Iota brand is the successor to Todd brand; I
believe Iota bought the designs, tooling, etc. and these have appeal
because of the relatively low cost per rated amp. They seem generator
tolerant.<br><br>
<dd>The Todd design is a "constant voltage" type charger,
however--basically an AC to DC converter with a fixed voltage output. In
my experience, the "75 amp" Todd type charger will deliver 75
amps only for a relatively short time when first connected to a low
battery. As the battery's voltage comes up that presents a sort of
"back pressure" which slows the rate of charge. That's not so
bad if one has utility power >always on< to drive the charger, but
if an engine generator is running...<br><br>
<dd>The inverter/chargers (with which we are all familiar) begin with a
"constant current" part of the charge cycle--aka bulk charge.
The charger is determined to sock the battery with the amperage we have
requested in the setup; I think a pulse width modulation is going on
where the charger hums up its voltage in order to keep the amps high even
as the back pressure builds. When it's time for the absorption phase of
the charge, the logic shifts to a "constant voltage" where the
amps are gradually dialed lower in order to keep the battery at the
target voltage so it can "absorb". Ignoring the float phase
which would come later, this overall charge regimen would be called CC/CV
for "constant current/constant voltage". The CV part of that is
not much different from what a Todd style charger does; it's just that
the Todd design does not precede that phase with a CC "constant
current" phase. <br><br>
<dd>Some free-standing battery chargers have a CC/CV algorithm but those
seem to cost as much or more than a comparably rated inverter/charger.
Check the Magnum mod-square multi's, Bill, such as their RD series. As
others on this List have noted, just the charge function is pretty good
and since the inverter circuit is not pure sine, that keeps the cost
lower. Built in time delay before it loads up the generator is an added
benefit. <br><br>
<dd>Jolliness,<br><br>
<dd>Mick Abraham, Proprietor<br>
<dd><a href="http://www.abrahamsolar.com">www.abrahamsolar.com</a><br><br>
<dd>Voice: 970-731-4675<br>
<dd>_______________________________________________</blockquote>
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