Just a quick update on shuffling the batteries. The battery that I moved from the number 1 position to the number 3 position is behaving exactly like batteries 2 and 4. The number 1 battery (was the number 3 battery) is lower than the rest while charging. Maybe it doesn't matter that one battery is always charging at a lower voltage but I feel better knowing that after moving the battery it acts like the others.
Mark
Santa Cruz
--- In
electricboats@yahoogroups.com, "luv2bsailin" <luv2bsailin@...> wrote:
>
> Hi guys,
> Maybe that few mA the Paktraker uses is enough to bleed off the surface charge. Are those lower readings showing up after the bank is charged, with no load? If so, that may be the case. It would be interesting to know what they read after running awhile. I would guess that should pretty well even them out, or at least swamp out any surface charge effects. The real test would be to graph out the individual voltages over time during a run and compare the slopes. If you run at a steady amp draw until you see a rapid increase in rate of drop (a "knee" in the slope), you'll have a pretty good indication of actual capacity at that particular amp draw. I don't know at what DoD that knee normally occurs, but I have seen it on several plots I've taken and would consider it the "darn-near-dead" (DnD?) point for all practical purposes.
> Anyhow, all my boat projects are on ice (literally) for the winter, so I hope you all don't mind me throwing my $.02 into the mix in an attempt at a little vicarious tinkering and troubleshooting. I haven't paid that much attention to the finer points of battery string management so I find this thread very interesting and educational.
> Cheers,
> Jim McMillan
>
> --- In
electricboats@yahoogroups.com, "Capt. Mike" <biankablog@> wrote:
> >
> > Steve:
> >
> > Ah. That explains it. It looks like you are seeing the same effect as Mark and I on the batteries where the Paktrakr takes it's power from. Be interesting to see how the HDM's change this when you install them.
> > Sent from on board BIANKA
> >
http://biankablog.blogspot.com> >
> > -----Original Message-----
> > From: Steve Dolan <sdolan@>
> > Sender:
electricboats@yahoogroups.com> > Date: Wed, 05 Jan 2011 09:57:39
> > To:
electricboats@yahoogroups.com<
electricboats@yahoogroups.com>
> > Reply-to: electricboats@: RE: [Electric Boats] Re: Battery Balancing (again)
> >
> > My Mistake Mike,
> > Since I'm using 2 PT modules both power feeds are connected to the first battery in each string of 6 (all in series) that would mean battery #1 (most negative) and #7 have the power feeds and read the lowest indicating the PT modules are pulling them down slightly.
> >
> > Sorry about that,
> >
> > Steve in Solomons MD
> >
> > ________________________________
> > From:
electricboats@yahoogroups.com [mailto:
electricboats@yahoogroups.com] On Behalf Of Mike
> > Sent: Wednesday, January 05, 2011 9:50 AM
> > To:
electricboats@yahoogroups.com> > Subject: RE: [Electric Boats] Re: Battery Balancing (again)
> >
> >
> >
> >
> > Steve:
> >
> > I have slightly different readings on my four battery bank. The most positive battery usually has a slightly higher voltage reading than the others including the lowest (most negative battery where the Paktrakr power is connected). I would expect the lower battery to be slightly lower in voltage because of the Paktrkr's 10ma load. Don't know why your most positive battery would also be lower though. If you don't have any load connected across just that battery it could be just coincidence that it is aging differently than the rest of the pack.
> >
> > Capt. Mike
> >
http://biankablog.blogspot.com> >
> >
> >
> > --- On Wed, 1/5/11, Steve Dolan <sdolan@> wrote:
> >
> > From: Steve Dolan <sdolan@>
> > Subject: RE: [Electric Boats] Re: Battery Balancing (again)
> > To: "
electricboats@yahoogroups.com" <
electricboats@yahoogroups.com>
> > Date: Wednesday, January 5, 2011, 11:10 AM
> >
> > When I tested the batteries last month I noticed the first and last battery were slightly lower than the rest of the pack. It wasn't until just recently that I was looking at the numbers and realized I hadn't disconnected the PakTrakr when we tested them. Parasitic load on the first and last battery.
> >
> > Steve in Solomons MD
> >
> > Hi Jim,
> >
> > I was thinking the same thing. Seems odd that we both are getting similar readings. Or maybe this is what happens with a two lead (+/-) charger.
> >
> > Is anyone using another brand monitor that monitors and the individual batteries? If so do you get consistently different readings on the first and/or last battery?
> >
> > Thanks,
> > Mark
> > Santa Cruz
> >
> > --- In
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>, "luv2bsailin" <luv2bsailin@> wrote:
> > >
> > > Mark/Mike,
> > > I've been following this thread with interest. Just a thought... have you independantly verified the voltages with a meter, or are you relying on the Paktraker readings exclusively? Since you both seem to be experiencing similar symptoms it might be logical to suspect the Packtracker of giving a false reading on channel 1. It would be simple enough to verify.
> > > Cheers,
> > > Jim McMillan
> > >
> > > --- In
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>, "acsarfkram" <acsarfkram@> wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > I went out for a sail today, gotta love Santa Cruz in January :-). I did notice before I went out that the pack looked similar to before I switched the batteries. That is; the #1 battery (neg. most) was reading lower than the rest of the batteries and the "new" #3 (was #1) was right up there with the rest of the pack. After sailing I plugged into shorepower and while charging the #1 had the lowest reading by .3 or so volts and the #3 had the highest reading - maybe .3 higher than the #2 and #4. This is just one day after switching the batteries, I'll keep an eye on them and let you know if I see any change.
> > > >
> > > > I was thinking of switching the batteries on the Kipoint with the batteries on the Dual Pro but that's 76 connections to undo and make!
> > > >
> > > > Mark
> > > > Santa Cruz
> > > >
> > > > --- In
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>, Mike <biankablog@> wrote:
> > > > >
> > > > > Mark:
> > > > > Â
> > > > > I have the same issue with the most negative battery and I also have a Paktraker installed. I'd be interested to see how your swapping the third and fourth batteries works out. I too wondered if moving the battery positions around might be benefical for balancing purposes. But, at 120 lbs apiece I am not eager to do this as an experiment.  Especially since the bank is behaving it's self and charging with the Dual Pro has all batteries finishing charging within minutes of each other.Â
> > > > >
> > > > > Capt. Mike
> > > > >
http://biankablog.blogspot.com<
http://biankablog.blogspot.com/>
> > > > >
> > > > > --- On Mon, 1/3/11, acsarfkram <acsarfkram@> wrote:
> > > > >
> > > > >
> > > > > From: acsarfkram <acsarfkram@>
> > > > > Subject: [Electric Boats] Re: Battery Balancing (again)
> > > > > To:
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>
> > > > > Date: Monday, January 3, 2011, 6:49 PM
> > > > >
> > > > >
> > > > > Â
> > > > >
> > > > >
> > > > >
> > > > > Hi Steve,
> > > > >
> > > > > Thanks for bring this up (again). The link to the balancer is timely as I'm currently dealing with a battery that is consistently lower in voltage during charge than the other batteries by .2 - .8 volts.
> > > > >
> > > > > The charger (Kipoint 48 volt) charges the string of 4 batteries as one 48 volt unit. I've tried turning off the Kipoint and hooking up a 4amp 12volt charger to the low battery. That seems to help but the battery eventually returns to it's lower state of charge. So far it has not tripped the alert system on the PakTrakr.
> > > > >
> > > > > The battery that is in question is the negative most battery and the one that the PakTrakr draws it's power from. I can't imagine the small draw (10mA) is enough to affect the battery especially since the batteries are almost always connected to a charger. Yesterday out of curiosity I moved the negative most battery (the low voltage one) to the #3 position and the #3 battery to #1 (negative most) position.
> > > > >
> > > > > Does anyone know if this might help? Do batteries get different levels of current when being charged as one 48 volt unit?
> > > > >
> > > > > Thanks, Mark
> > > > > Santa Cruz
> > > > >
> > > > > --- In
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>, "Ron" <rlgravel@> wrote:
> > > > > >
> > > > > > If there is a single set of two wires for each battery in the pack, then I think a bridge rectifier for each battery would be monitored by the electronics of the circuit. It's the only way my mind can see individual balancing of the batteries, maybe someone knows just how the chargers work. ??
> > > > > >
> > > > > > --- In
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>, Steve Dolan <sdolan@> wrote:
> > > > > > >
> > > > > > > Hi Mike,
> > > > > > >
> > > > > > > I consider my Genset as my backup since I can charge and run the motors off of it. I'm not sure if I understand how the charger can identify individual battery state of charge. I had always felt that it was measuring the total pack state, in my case 144v, and if one battery was over charged it couldn't see that one was undercharged. In the case of a charger you would have to individually charge a low battery. The Equalizer systems would measure individual batteries and shuffle power between them to balance the pack. Yes from what I can tell there isn't much to tell on the HDM all is well other than looking at the PakTrakr which can tell the individual state of charge.
> > > > > > > As to the different battery types I thought it would only balance the batteries to whatever the high/low range was. If the charger was set to maintain a 13.8v (165.6v pack V) per battery and the lowest one in the pack was 13.3 wouldn't it balance the pack to an average say 13.6 then the charger would raise it to 13.8 as it balanced?
> > > > > > > As to the cost I received a quote of $120 for the 48 and $110 for the 36. I would need 3 of the 48's and 1 of the 36.
> > > > > > > This particular manufacture can handle as many batteries in the string where the PowerChek's was limited to I believe a max of 10 batteries and was also at only 2v shuffling.
> > > > > > >
> > > > > > > Please correct my understanding of the system balancing if I'm wrong and if there are any other specific questions I plan on asking some additional questions and will add them to my list.
> > > > > > >
> > > > > > > Is the shuffle rate (5a) variable?
> > > > > > > What about Lithium's?
> > > > > > > What does the Solid green indicator indicate? Balanced or operating?
> > > > > > > Does the Green light pulse/flash during balancing?
> > > > > > >
> > > > > > > If there is enough interest I would ask about a group buy.
> > > > > > >
> > > > > > > Thanks,
> > > > > > >
> > > > > > > Steve in Solomons, MD
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > Steve:
> > > > > > >
> > > > > > > I think the short answer is it's all good! Each approach has some advantages and disadvantages. For example I've got the Zivan NG-1 across the 48 volt bank I added the Dual Pro charger because I was concerned about bank staying in balance. The upside is I now have two battery charges and as a cruising sailor I like to have backups. But, I also found the Dual Pro does not charge as fast as the Zivan so it means a longer generator run time. Something I try to limit as much as possible. So I came up with a plan to use the Zivan through the bulk charge cycle and then switch to the Dual Pro (or solar and wind) to finish topping the bank off.
> > > > > > >
> > > > > > > However, I can see where using a battery balancer like the HDM EQ48 can have it's advantages. For example now when the boat is laid up for the winter I'm letting the solar and wind turbine keep things charged up. Like the Zivan they are connected across the whole bank. Though I try to get there weekly to check on things, work on projects etc... When I do I also plug in the Dual Pro just to make sure things stay balanced. During this time a battery balancer like the HDM unit would come in handy because it would balance the batteries automatically. But HDM unit only has a single pass/fail LED. With the Dual Pro I have a bar graph display of each battery in the bank and I can tell instantly when one bank is considerably down or takes longer to charge compared to the other batteries and of course the HDM can not act as a backup charger. But, it would help keep things in balance when using ANY across the bank (charger, solar, wind) devices.
> > > > > > >
> > > > > > > I do have a few questions about the HDM unit though. How do they handle the different voltage requirements for Gel, AGM and flooded batteries? When I ordered my Zivan and Dual Pro chargers I had to specify what type batteries they would be used on. My other question is how much does it cost?
> > > > > > >
> > > > > > > Capt. Mike
> > > > > > >
http://biankblog.blogspot.com<
http://biankblog.blogspot.com/>
> > > > > > >
> > > > > > >
> > > > > > > --- On Mon, 1/3/11, Steve D <sdolan@> wrote:
> > > > > > >
> > > > > > > From: Steve D <sdolan@>
> > > > > > > Subject: [Electric Boats] Battery Balancing (again)
> > > > > > > To:
electricboats@yahoogroups.com<
http://us.mc840.mail.yahoo.com/mc/compose?to=electricboats%40yahoogroups.com>
> > > > > > > Date: Monday, January 3, 2011, 12:50 PM
> > > > > > >
> > > > > > > I had asked about battery balancing a while back with no responses. I've found this company
> > > > > > >
http://www.hdm-sys.com/products/equalizer.php> > > > > > > The general opinion here seems to be multiple battery chargers rather than a "shuffling" of power between batteries. Can anyone give me a reason to choose one or the other or why shuffling isn't a better idea?
> > > > > > >
> > > > > > > Thanks,
> > > > > > > Steve in Solomons
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
>
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