My battery soc

jcheil

Re: My battery soc

gww1 wrote: »

J
I have just a mate not a mate three so I don't really know on you system. On my system it is in two places. As I run in hbx and don't sell I may be doing something differrent then you.

One of the low voltage disconnects is on my hbx menue. To get there I push advanced, put in the pass word "141" go to mate, go to hbx, and I think the grid use setting is first and scrolling down once gets me to the time value setting. grid use voltage is what voltage the loads switch to grid or (low voltage disconnect).

The other setting is (I believe) the same except you go to fx instead of mate and then go to inverter, your settings are there.

I hope this helps
gww

10-4, I thought you were talking about the LVD for the inverter (to shut down).
I wish there was a setting for TIME on that. I know once or twice on my old system, if I had a BUNCH of loads start up at the same time I would MOMENTARILY drop below 48.0 (where I had the LVD set) and that would shut down the inverter. It would come back up a few minutes later (at the reconnect point) but was annoying.

gww1

Re: My battery soc

Blackcherry
Good ideal on the clamp meter. I had the setting at 44.8, I have lowerd them to 43.8 volts and on hbx one half hour holding at that voltage. the pump when it kicks on is only for a very short time. There is some inconsitancy of when the grid picks up the loads. I do have one reading on the cc that says the low voltage was 44.7 but most times it is above 45 volts. The battery rebounds to 47 volts really fast. 40 amp draw seems to be the the problim area. it was holding 45.7 volts with a 30 amp draw. I have used about 460 amps from the battery. I am going to keep lowering the low voltage and see if it makes a differance. as it stand now I can never go below 50 percent of the battery even if I wanted. I have been watching the voltage compared to the chart from gb's web site and it seems to be holding steady but about .2 or .3 volts below what the chart has for the percentage of charge. This is with only a very short rest not a three hour rest. That leads me to believe the battery is on track to where it should be. Now to find a way to use the power if I needed it. This is of course independant of sg readings since I screwed that up buy adding water at the very end of my last charge session.
Well I am going to run out and see if it is holding the load after my last lowering of the voltage. More in a bit.
Thanks
gww

Blackcherry04

Re: My battery soc

At some point your going to have to realize that all systems have limitations. You seem to be still dancing around the problems.

1) I would load shed the pump at 47v with a VCS and transfer Relay and automatically move any problem loads to the grid. You can set the high transfer at 49v or so when you get Sun and transfer back to the battery. $150 is a heck cheaper than either killing your system. It's not only the Battery, your Inverters are probably @ 80% or so efficiency at those low voltages , look for repair costs to mount up as you stress them.

I'd love to run my Central A/C 24/7 on the battery, it will never happen unless I am willing to spend $20,000 to run it. I could go to Mini Splits and make something work, but again, more money. The answer , switch it back to the grid unless I am producing enough power from the Sun. You can also change the pump to a more efficient DC pump.

gww1

Re: My battery soc

The trimetric said 23 something amps, one inverter pos said 12.26 and the other said 13 amps and the single negative said -26 amps. Over all the readings for the trimetric was a bit lower and the mate said .6 Which would be about 13. Makes me wonder if I am somehow missing the imput of one of the inverter. If that were the case though I would be at 100 % convertion. I just worked on that inverter so I better go look if I connected it back to the mate. I did though cause it is running 240 volts and responding and I did a repoll just the other day. It is about the correct missing data for on inverter though. dang, anouther mystery. I guess the clamp meter readings wheren't that for off from the trimetric.

The battery was holding 46 volts with the 23 amp load.
gww

gww1

Re: My battery soc

Blackcherry

At some point your going to have to realize that all systems have limitations. You seem to be still dancing around the problems.

1) I would load shed the pump at 47v with a VCS and transfer Relay and automatically move any problem loads to the grid. You can set the high transfer at 49v or so when you get Sun and transfer back to the battery. $150 is a heck cheaper than either killing your system. It's not only the Battery, you Inverters are probably @ 80% or so efficiency at those low voltages , look for repair costs to mount up as you stress them.

The pump never causes me issues except when I try to go below 50% discharge, however what could I type in a search engine to figure out how to do what you are saying to do. (the transfer thing not the dc pump) I know you can do about anything once you know it can be done but at my knowlage level I am going to have to do a little research cause I only know what you are talking about in the most general sence.

Thanks
gww

ps I would run the pump on grid except for power outages but to hard to switch back and forth. I know about cost, it wasn't that long ago that I had that pump replaced and it cost me $2200 to do it.

Blackcherry04

Re: My battery soc

This what I am talking about. With a active low switch when your battery drops to the set voltage the switch engages a relay ( transfer switch, contactor ) that moves the pump input to the grid. When the voltage of the battery raises back to another set voltage the pump input goes back to the battery.

http://www.solar-electric.com/catalogsearch/result/?q=vcs&cat=0

You don't want to set it to low, I'd do it when the battery is at say 48 v and switch back when it's 49 or 50. There is a 3 second delay in the switch, but you may have to put in a delay cube timer so you don't short cycle the pump if it was the load causing the voltage sag. These are the kind of tweaks called work arounds, no difference then using a AGS to start a generator.
.

gww1

Re: My battery soc

Just stepped back in and have not had a chance to read what you posted yet. I did however finaly check my mail and I did recieve the vials you sent me. I can't thank you enough.
gee

gww1

Re: My battery soc

Blackcherry
When I put my ssr on the hot water heater it was all simple except for one thing. I had to run sence lines from my cc to my ssr. It wasn't so bad cause I had to trench a feed line to the house for my sub panel and I just put the sence line (I used some fairly thick aluminum direct burial wire) in the trench with the feed line. I believe using the mvc would entail something simular and be a big job. It seems I could use one of the cc auxilary to do what the mvc would do but still would have to trench again. If I trusted electric devices I could use two ssr with the cc and inverter aux and have one wire from the main panel and one from the sub panel feed the pump but it would be bad if they both kicked on at the same time.

I can't believe the price of plain old manual transfer switches. I wouldn't mind being able to just move it manualy. I wan't to try my non-inverter generator on my outback inverter to see if it would hold good enough to charge batteries through the inverter but would need a transfer switch. I believe I am going to have to look though all my junk and see if I can come up with enough small boxes and breakers to make a couple of them or at least one to test the generator and if it doesn't work move to pump and just transfer it manualy. Run the pump from the grid except when it is down witch is never.
gww

gww1

Re: My battery soc

I think I am going to stop the discharge at 70 % discarge and start the recharge. I don't know if this is smart or dumb. I can't get sg readings and just in case the capasity is down, maby better safe then sorry? The rebound volts have consitantly been .2 or .3 volts lower from the the percentage chart volts. This is from short term rebound though. That means I will be leaving a little over 80 amps in the battery from a full 80% discharge. That is a 12% margine of error. If the batteries have lost 12% capasity it would be perfect if not I stoped to early.

Question
If my goal is to deep discharge and then recharge in the hopes of increasing capasity/forming plates, is stoping early When I am not sure what I am dealing with a mistake?

I am at 35% discharge right now.

Thanks
gww

CALLD

Re: My battery soc

Hi gww1,

While I may not be one of the boffins on this site, I've been watching quietly from the side and thought I had to say something because the problems you are experiencing bare a remarkable similarity to the problems I had with my previous set of batteries. While on a much smaller scale to your setup the symptoms were the same.

Low battery voltage under moderate loads, difficulty in determining state of charge by SG, voltage etc. In my case it was impossible to tell why my old set were performing so badly. The only way for sure would have been to compare them directly to a brand new identical set which was not possible. All I know for sure is the moment I replaced them with my new AGMs battery anxiety has instantly become a thing of the past.

The hard reality is a change of battery type may be your only saving grace.

Alternatively you could try putting them on float charge for a week or two. That momentarily boosted the performance of my old set, but it wasn't long, only a few days to be exact before they were back to poor performance...

Blackcherry04

Re: My battery soc

70% sounds fine, going to 80% is not going to change the capacity. The Idea is to pull it deep and involve as much of the plate as you can and have a good recharge to full. Once you think it is full ( by Battery Monitor or whatever you use ) then check the SG's to verify. If you do this as often as you can and look for Improvement in time, ending amps, Amp hrs removed and Replaced. After 10-12 of these full cycles you should see some improvement.

BB.

Re: My battery soc

Question--How far do you "Need" the battery to discharge... Do you expect to supply your loads down to 50% discharge? If so, then I would not feel bad about discharging to an estimated 50% SOC.

If the battery "fails" before it gets to 50% discharge (or X hours of ABC loads), then the battery bank is not meeting your needs.

-Bill

gww1

Re: My battery soc

Calld
Thanks for the responce. The batteries are barily a year old, if I replaced them I wouldn't get to see the fruit of my labor cause my wife would have killed me. I got to get what I can and that is all there is to it.
Cheers
gww

Cariboocoot

Re: My battery soc

BB. wrote: »

Question--How far do you "Need" the battery to discharge... Do you expect to supply your loads down to 50% discharge? If so, then I would not feel bad about discharging to an estimated 50% SOC.

If the battery "fails" before it gets to 50% discharge (or X hours of ABC loads), then the battery bank is not meeting your needs.

-Bill

Different situation Bill.

What he's supposed to be doing is discharging the battery to its maximum and then fully recharging it in order to cycle it and complete forming the plates so that it has full capacity. How much it is discharged in normal use after that is another matter. Unfortunately this commission charging was not done at the start (or at least not completely) due to poor info from the battery seller/maker. Now he's trying to make up for the deficit.

The plan of discharging deeply and then recharging completely can only be measured by SG now; no battery monitor will work because they are based on programmed values. These values would be a wild guess at this point.

The 'opportunity loads' should be removed completely for this process, especially as they apparently drop the charge rate to 5% when active which is too low. It should be discharge/recharge only; no loads running while charging is going on. Removing erratic and/or irregular charge sources would be a good idea too.

Unfortunately this whole thing requires a boring, systematic approach that will take some time to complete (many days) before the battery can be put 'in to use'.

gww1

Re: My battery soc

Blackcherry
I couldn't even wait that long. I was having a hard time discharging them anyway cause I had to watch the inverter and keep interceeding. I took 549 amps out of it. I have it charging with the sun at 83 amps and am trying to decide if I want to up or lower that. The rolls site you posted said a long 5% charge was better in some situations.

I don't know if I can go through ten or tweleve cycles like this. But I am going to do some. and do some watching also.

Thanks
gww

Blackcherry04

Re: My battery soc

Gww, you have to let your pocketbook be your guide, I'd suspect that GB will be glad to sell you a new battery. Just try it for a few full cycles. Coot has been trying to get you to this place for a week. You have several different things going on here, plates, stratification being two of them. It's the long absorbs and heavy gassing that are going to help the most. Watch the charging and make note as it goes from bulk to absorb and record it ( time and amps & and Amp hrs replaced ) . You should be at about 80% +/- at the transition, then watch the absorb, watch the time and amperage drop and the ending amps. Your going to have to look for Improvement.

A year old Fork Lift Battery should not be acting this way. As BB said it's all about loads and your expected DOD.

gww1

Re: My battery soc

Bill
I don't think I have been discharging even to the 40% discharge 60% full range most times but I guess the truth is I am not really sure. My instinct is that I haven't been going as low as 70% charged. Before doing this I though I was taking 50% out of the battery.

I really don't need any discharge, as I have the grid and not using this is probly still cheaper then using it even though its payed for. I would like to know what it could do If I ever did need it. I also as a matter of pride would like the things to be as perfect as I can get them. I really want the battery the best I can get it and the low sg and expecialy the low cell has worried me. Coot believes I may have hurt the battery and this may or may not help.

Mostly I am expermenting with things I enjoy (jeezz) but like any hobby, I ain't rich enough to really suffer the loss of a battery expecialy if I cause it. I though I had most of my stress in check when I started just making sure it got a good charge every ten or less days but I never got the sg right. I had decided to live with it cause it wasn't hurting me too bad. Mostly I say I am here cause I am still learning and willing to find out if I really am deafacit charging and ruining something I can't afford to ruin. I think I am over charging the other half of the time.

To your point, it would be (I think) a very rare thing if I needed to go more then 50 % on the battery. I do want to find that mediam where I can use what I have to the max. Before I had the oppertunity load my production was being cut at 18 kwh now I can get 30kwh but hope I am not harming thing and not smart enough yet to know.

I am sure you didn't need all the above but some of it was working out my own thoughts on the subject.

If I get your points: It is why overly stress the batteries if it is not needed? If nothing is wrong with them I agree, If I am doing something wrong to make that not happen I need to fix it and learn to charge in a manner where I am not stressing the battery.

Thanks for the question I bet you wish you didn't ask.
gww

gww1

Re: My battery soc

Coot and blackcherry

It aint the money if by money we mean losing solar while discharging and using the grid while charging. That could ad up to what 5 buck a day.

It is the money if talking about the battery. I got to try and get that right and by the way, my efforts to do so have been honest and time has been put towards it up to my skill level.

This discharge and recharge is a pretty long prosses and I am committed although it will get spaced here and there due to things like taking my children to the airport fri. or openning my dads house for the furnace guy to get in. Things I just can't get out of. The first was probly the worst due to not knowing how things would react or how fast my loads would draw down the battery. I have learned a few things. Like may be turn some more lights on in the beginning.

I get your point coot on the sg readings, I kind of screwed that up this round and that was definatly one of the nerve racking things making it hard for me to make myself take th batteries lower this time.

Next time will be better.

I still intend to watch how many amps have left the battery but am I correct in thinking that during discharge I really don't want to put a long term high draw above 40 amps if I intend to relie a bit on the amps that have left. In other words I don't want to leave the water running so I am drawing 50 or 60 ams out continually cause I would have to count different due to puekrt effect or what ever its called?

If I get a pretty decent 40 amp draw, then as the battery goes down I can take sg readings and compare them to the chart and get a round about ideal.

Is this a correct prosses?

Coot, You say I need uninterupted amps. Do I wan't a 15% or higher charge rate for the times I can get it?

Thank you guys for your help and if I am missing something please call me on it.
gww

Blackcherry04

Re: My battery soc

If I built you a drag motor for a race boat and I told you to put 4 , 1/4 mile runs on it at 8,000 rpms, but you decide that you want to do 2, 1/4 mile runs at 3,000 rpms. It blows the on the first wide open run, you going to blame me ??

I don't build race motors, you could probably run that motor for a long time at 3,000 rpm, but it would not be ready to use in a race.

You don't have to go to 80% dod all the time but you have to get your battery ready to function at full capacity and I don't believe you are there. If you don't get it functioning now, in 4-5 years, it won't have 300 amp hrs in capacity. You may have already lost some that cannot be reclaimed, but not to to try to get back is your call.

I did the same thing with my Surrettes, I played with them for 6 months, they had half of the capacity they should have, SG's all over the place, I was EQing them every week. and a big voltage sag, it was either get them better or get rid of them. As soon as I started taking them to 50+% and hammering them everything started to change. Where I use to have to go to 11 ending amps, it's now 30 amps, I still have some sag, but it's manageable, they charge faster. The SG's are staying up because I am getting good mixing in absorb. It had to be the plates, Steve Higgins from Surrette gave me that clue that their plates take a long time to form. The longer they take to form, the longer life of the battery.
.

Cariboocoot

Re: My battery soc

Weird how I was thinking of an analogy almost identical to the one BC04 posted!

I have not tested charge acceptance on forklift batteries, but I suspect it is worse than on smaller deep cycles. This means they need time over Voltage or current. In other words Absorb at 60 Volts over 5 hours is better than Absorb at 62 Volts over 4 hours (or whatever; not actual data just relative to the function) and Bulk at a maximum of 10% current over 4 hours is better than Bulk at a maximum of 15% current over 3 hours (same disclaimer). Higher current increases the charge rate but also increases the power going to heat, and there comes a point when adding Amps does more to heat the battery than charge it. This you don't want. But you especially don't want anything keeping the charge rate way below that basic 10%, particularly not while your still trying to get the plates fully formed.

The sheer mass of these batteries presents some problems with RE use which is why regular EQ is often recommended for them; to correct the steadily decreasing SG brought about by not being able to follow the prescribed use/charge pattern. Once you get past the initialization stage they will function more 'normally', although I still would not recommend having any opportunity load decrease the maximum charge rate. The opportunity is when the panels can put out more power than the batteries need, and that will not occur below Absorb Voltage and possibly not until you're quite a ways into Absorb. That is the second step: measuring how much 'extra' power is available when, and figuring out how to best make use of it.

gww1

Re: My battery soc

Blackcherry
I really am trying to listen to everyting you say. I may get confused when to things are mentioned, example: "You may have already lost to 60 percent capasity", "Take it down to 45 volts". "Take it down to 80%", "Watch the sg to figure where you are". I take all these things put them to gether to the best of my ability and try to do what I thought you and coot ment. I did here you when you said it probly wouldn't hurt the battery to go the full way but got scared anyway.

I am a little slow on prosses, like waiting till the trimetric was hooked up before starting the charge discharge. I may have a thing or to get in the way once in a while, but in the end I know I need the help and am thankfull when I get it. If I do get srewed up along the way it is cause I am trying to understand what you are really trying to say and not just cherry picking one statement and laying the blame on that.

If I ever feel confident of what I believe and it is differrent then what you are saying I would be up front in presenting that. The rest is just questions to try and get all you can give me untill I understand. I have a tendancy to ware people out till I understand.

I am charging now and will discharge next. And I thank you guys for helping. I ask for the plan of attack, I am not looking for any one to blame and I am hoping to not need a battery for as long as possible.

Thanks
gww

Blackcherry04

Re: My battery soc

"Take it down to 45 volts". "Take it down to 80%", "Watch the sg to figure where you are".

These are the 3 things that have to come together so you know what you battery health and capacity is. These are the 3 things you have to verify and be in tune with. You'll never be able to manage your battery without them. If you take out the % from the Battery Monitor you can still judge the place you are at, because you know your constant, the place you started with the high SG level of 1.280 +. Voltage only works if you have a healthy battery, because one sq inch of plate can give you voltage. No one knows if the Battery Monitor % is correct yet, because it's untested. Once you get it calibrated you can rely on it more.

gww1

Re: My battery soc

Coot
The turbines are the canundrum. I built them, they are the only thing my grand children like, they only make a differance in two ways to the system. One is the opertunity load and if it wasn't that it would be a divertion load that would work the same way but give nothing and two, they really only effect the system in fall and winter cuase they really give nothing in summer. I really don't understand how the turbines hurt unless it was a really rare day that they raised the charge rate above 10 percent. I do understand the opertunity load and the way you do it by making sure it is not stealing from the battery but is true excess production. I am willing to short out the turbines for periods or unhook loads from the batteries but I have a tromendous amount of work in the turbines and towers and really like them and are proud of them. I can run test with out them but really want to find a way to inigrate them into the system.

When the battery hits absorb, it will only stay in absorb as long as the amps are high enough to hold the voltage. I now have the opertunity load half a volt from absorb and could put it closer. If I put it .1 below absorb wouldn't I basicaly be in absorb when the hot water kicks in. It doesn't really have to steal from the battery cause it doesn't kick from off to on, it only sends excess from the battery that would drive the battery to a higher voltage. It starts out by sending 1% then 5% and so on but doesn't drop the battery voltage. The reason it droped the amps from 60 to 40 earlier was because the voltage it was trying to hold was 3 volt before absorb. I can disable everything but charging and discharging during this regament but need it in the end and honestly can't see the differance to the battery from the way you are doing yours. If I am missing something please tell me. Again I ask questions so I can know, not cause I think you don't know.

Any way, I will try to keep the batteries charging at 10% If during the day the sun is intince and I am running no loads it will be closer to 12% and when I go back to normal use, it will be closer to 8% with loads. I might miss it up or down at the end of day like now cause I start at about 7 ac amps through the inverters charger and slowly increase as the solar decreases.

Blackcherry

Those are the things I will try to watch and I will try to remember to use the clamp meter once in a while.
Thanks

CALLD

Re: My battery soc

gww1,

I've heard that a simple way to test the health of your batteries is to test the internal resistance once they are at or near 100%SOC.

1st thing you need to know is what the manufacturer says it should be. My 260AH AGMs are 0.0035Ohm per 12v or 0.0006 per cell. For 24v that is 0.007Ohm.

Then the following simple test can suffice if you don't have a professional AC tester.

1) On a fully charged bank initiate a C/20 discharge rate (in my case 13 amps) and allow it to go for an hour,
2) Check the voltage (in my case it was 25.4 volts with the 13 amp load on)
3) Add a C/5 load to the existing C20 load (in my case I added a 1200watt load which would have been close to C/5 or 52 amps).
4) Record the instantaneous voltage drop (in my case it was a 0.5 volt drop down to 24.9v)
5) Using Ohm's law I could estimate the batteries internal resistance by using R=V/I which got me to 0.0096 Ohms at the points where the volt meter connects to the battery. According to the manufacturer it should be 0.007 Ohms but taking the resistance of the connections and the wiring into account it looks pretty spot on. This is a good indication that the plates are in good condition and that sulfation hasn't occurred.

In your case a C/5 load on a 48v 800Ah bank may not be feasible (7680 watts), but if you can manage a C/10 load that could still get you some answers. Flooded batteries have a higher IR than AGM's in general so the same test could work with lighter loads, just make sure the surface charge has been removed from the plates first...

gww1

Re: My battery soc

Calld
Congradulation on your new batteries. I hope they work well for you. I would have to have two people for what you suggest cause I can't controll my loads quite as easily cause when my inverter is on, my most of my whole house is on in a differrent location (including phantomn loads).

I am getting a feel for what is on and what it draws but have found the mate to be really off and haven't had the trimetric long enough to trust its readings though I do believe it is probly close on what is is saying that is leaving the battery instataineously. (Yes my spelling sucks and the last spell checker I tried to load crashed my computer, so I make everyone live with what I do).

I don't really know the differance between sulfation and stratification. I do know from reading the differrent web links that my battery has more of the stratifacation symtoms. IE low sg and a higher voltage, I think.

I like that your suggestion is in writing and unless my computer crashes, I have this thread set in my favorites so I can refere back to it, and not lose it. I do imagine that if I checked with the manufactuer, That my internal resistance would be much higher then your as even before I bought this battery I knew that forktruck batteries are famous for voltage drop under load. I bought it cause it seemed that I had a chance to get the most life and most amp hours for the price. The other way that I heard a forktruck battery make you pay is with a high self discharge rate.

I tried to set it up where I had a little project that I was interested in and that kept me with little chores to do and maby give a little back or at least didn't add to the money draw, for my retirement. When I was a little younger I thought I would like a green house and maybe try aquaphonics but didn't want to do like dad where every new building you added increased your monthly bill cause you added anouther meter to run it. My plans don't always work, I got chickens and them little suckers can eat more then I get back from them. Built a couple bee hives out of used lumber. I am just screwing around and trying to do things that may not work out but don't put to big of a draw on my resources.

Man I always here that agms have so funny quirks when used with re. I really hope they work out well for you. I don't know anybody but me that does this stuff so mostly I have to relie on other peoples experiance, like yours, cause I only have first hand knowlage with what I am doing.

I did buy straw from an old farmer the other day that had a 12000 watt grid tie aray that he had some one else do all the work and with the 2 dollar a watt that the electric company gave him and the tax rebates he said he only had around $7000. of his own money in it. I did all the work myself and couldn't come close to being as good a deal as that. I never claim to be smart.

Thanks
gww

CALLD

Re: My battery soc

gww1, thanks for the good wishes - I really hope they do at least make the manufacturer's claims...

Wow I would love to retire with a set-up like your's one day, just not sure if I'm in the right line of work to ever afford it though. But as they say where there's a will there's a way...

I see, unless you can de-couple the rest of your house from your system for long enough to do the test there's just going to be a massive amount of guesswork and trying to get a feel for things as you say.

I also suspected stratification with my old set, but as many folks on this forum have said that gassing during absorb phase is supposed to sort that out. I even tried shaking my old batteries but it did nothing to the SQ after charging.

2nd thing I suspected but could never prove was that polarization was the culprit - the large voltage rebounds that you also notice was what lead me to suspect that.
I knew my old flooded batteries had glass mat seperators between the plates and I couldn't help wondering if they somehow kept the electrolyte from mixing properly. To add to those suspicions even further was that SG did climb eventually if they were allowed to sit on float charge for a week or more.

But if that is the case then what use are batteries like that? I mean a day is 24 hours not 240........

gww1

Re: My battery soc

calld

But if that is the case then what use are batteries like that? I mean a day is 24 hours not 240........

Which is probly an issue I am going to have to deal with forever, also.
gww

gww1

Re: My battery soc

coot or blackcherry
What do you think? Is it important that I let the battery rest before starting a new discharge cycle. I would like to start it cause I may be able to time the discharge to match some solar charging instead of having to use pure grid like I did this time. I don't care enough not to use the grid if that is what is best. Do you think it hurts to just start discharging?

The battery is 78.8 degrees. trimetric says full. battery has absorbed for 7 hour and is only accepting 4.6 amps.

cell 24 is 1.280 and cell 8 is 1.290 I don't believe they will go higher unless I use eq voltages.

Thanks
gww

Blackcherry04

Re: My battery soc

gww1 wrote: »

coot or blackcherry
What do you think? Is it important that I let the battery rest before starting a new discharge cycle. I would like to start it cause I may be able to time the discharge to match some solar charging instead of having to use pure grid like I did this time. I don't care enough not to use the grid if that is what is best. Do you think it hurts to just start discharging?

The battery is 78.8 degrees. trimetric says full. battery has absorbed for 7 hour and is only accepting 4.6 amps.

cell 24 is 1.280 and cell 8 is 1.290 I don't believe they will go higher unless I use eq voltages.

Thanks
gww

Fire it up, start getting those deep cycles on it. The 4.6 amps seem to be lower than you need to go. Write those cells SG's down and start with a new constant, it's the place you want to return to at full charge. If you begin to see improvement, you know your on the right track. Pick a couple points, say 80% soc and record the voltage and sg level. Make yourself a little chart and you'll have a reference. If your at say 60 % soc, you know the voltage should be 48.8v under load with XX amp draw.

I have a Voltmeter that is easy to read out in plain sight, at 9:00 in the evening, I know I have to be at 12.4 v to make it through the night and be at 11.9 v in the morning, it has a low voltage setting where it blinks the voltage if it's below 11.9v, it's obnoxious, it cannot be missed and very bright. I know if I am charging the volts have to be at 13.6 to make it through the night. It becomes a simple thing no matter what metric you use, amps, volts, soc, dod, SG or whatever you use. If it doesn't do what I think it should, then I look at what I need to adjust.

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gww1

Re: My battery soc

Blackcherry
1.280
thanks
gww