Charging with Classic

Started by asdex, February 18, 2018, 02:53:32 PM

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asdex

Hi, I see this information on another solar site and wanted to check what Midnite Classic uses think.
Battery Charging Part 1.
Yes you are killing your batteries if you use Solar to Charge them and follow battery manufactures recommended 3-Stage Charging Voltage Set Point. Stop that stupid, you are killing your batteries. You are sheep being led to slaughter. Step out of that line. All it takes is one Step to the RIGHT.

It is not that battery manufactures are wrong or misleading you, It is the application the manufactures assume are wrong. They think you are using a commercial AC Powered Smart Charger with unlimited time and power. Wake up you do not use commercial power or AC chargers expect once a month for maintenance on a generator right? You use Solar which is a very SOFT SOURCE of limited Power and Time. You got just 4 short hours in 24 hours to get the job done. Guess what?

Greater than 90% of all of you are killing your batteries from deficit/severe under charging, and following the manufactures recommendations are only making it worse.

With a commercial charger you start charging in Bulk until you hit about 80% SOC, then switch to Absorb which lowers the voltage a bit, current slows down and tapers to 2% of C. (about 6 clock hours) then you switch to Float and your battery continues to charge overnight and becomes saturated and fully charged by morning.

Well guess what? It is impossible for you to fully charge a lead acid battery on Solar unless properly oversized by design which you likely failed to do to start with. Even a properly designed system is going to come up short in winter months. There is just not enough Sun Hours in a Day to fully Saturate your battery.

Battery manufactures are getting slammed with warranty claims from Renewable Energy users. The claims are a result of chronic under charging and sulfated batteries. Many manufactures have revised their charging procedures for RE users. They have done away with Bulk Absorb, and Float voltage Algorithms. Today they aim at Maximum Smoke. Trojan calls it a Daily Charge of 2.47 vpc which use to be roughly Equalize voltage levels. What they are doing is forcing your Charge Controller to operate in Bulk mode or Max Smoke from Sunrise to Sunset. Still may not get your batteries fully charged. But still significantly more power stored than setting the voltage to a lower value.

So what do you do? Well what you should have been doing from the start. Use your Temperature Compensating Hydrometer to find the right voltage if there is one. For roughly 90% of you there is No Voltage High Enough you can set your controller to get the batteries fully charged up, because you do not have enough panel wattage to begin with. For those of you who find yourself in that situation, all you can do is limit the damage by cranking the voltage to MAX, and then every couple of day run the genny to get your batteries back to 100%. Don’t like that idea? Tough Titty said the Kitty, you made your bed, now sleep in it.

For the rest of you where you do have enough power panel wattage to get fully recharged most of the time, you are not going to use the manufactures recommendations, you are going to find the exact setting using your Hydrometer.

So that leaves you with only 2 voltages to concern yourself with Daily Charge on your Charge Controller, and EQ on your AC charger used on your generator. OK at this point you may be asking yourself how I do that when my Charge Controller is a 3-Stage Controller? The answer depends on what Controller you have:


• Set Bulk = Absorb = Float if your controller allows. Initially set it to 2.47 vpc
• If your Controller will not allow you to set all three modes to the same value start by setting Float to the desired voltage like 29.6 on a 24 volt battery system. Then set Absorb as high as the software will allow that is less than Float like 29.5 and 0 minutes or hours. Set Bulk like Adsorb except try the same as Float first, or lower like 29.4


What this is doing is forcing your controller to behave like a simple Constant Voltage â€" Current Limit algorithm. (Max Smoke) Basically your Controller will stay in Constant Current charging until the battery reaches the Float Set Point. When that is reached the current will taper off, and if you’re lucky enough to have enough Sun Hours and panel wattage you should see that current taper down to about 1 to 2% of C indicating full charge. C is the battery AH specification at the 20 hour discharge rate. So if you have a 100 AH battery would be 1 to 2 amps. The point of doing this is to get as much energy as possible into your batteries with the very limited amount of time you have with Solar. If you have the system designed properly and lucky you will get back to 100% SOC, but do not count on it.

So how do you know if it is right or not? Pull out the Hydrometer, that is what you bought it for. When the Sun starts to set low in the sky, check your Specific Gravity. If it is too low, you need to raise the voltage, if voltage is maxed out and you still are not fully charged up, GUESS WHAT? You do not have enough panel wattage.

If you have enough panel wattage, you will find the right voltage. But do not relax, your job is not over. Conditions change by day, week, month, season. What worked last week may not work this week.

So let’s get started on a proven method that works. First order of business you have to have a Temperature Compensated Battery Hydrometer, and you must learn to use it and use it often. You cannot use a volt meter to tell the State of Charge in a battery. Voltage is only an indicator. It can only tell you if something is way out of acceptable limits like Equalization or equal voltage between cells, or if your batteries are really low. But a volt meter will not tell you the SOC. There is only one way to measure SOC and that is with a Temperature Compensated Hydrometer. Don’t worry they are not expensive, less than $10. Deka makes a really good one and you can order it online. So get to it. To learn how to use a Hydrometer read this.

OK regardless of how new or old the batteries are we need to get them fully charged and Equalized. This is best done with a generator, and if you are off grid, you had better have a generator and a commercial AC charger. A generator is required to perform Preventative Maintenance like equalizing your batteries as needed (about every 4 weeks or as needed). And carry you through cloudy days. If you do not have a generator you have no choice but to use your controller, but it could take several days using your controller. EQ can even take 12 to 24 hours with a generator.

To Equalize is a controlled over charge. Check your battery manufactures specifications for the correct EQ voltage but it should roughly be 2.5 to 2.6 volts per cell. So if your battery voltage is:


• 12 Volts = 15.6 volts
• 24 Volts = 31.2 volts
• 48 volts = 62.4 volts


To learn how to equalize read this. You are going to need the Hydrometer. Did I mention you must have a Hydrometer?

OK now that you have EQ time to set your controller voltages. Take note this is a starting point, not a definitive. Initially set your voltages to 2.46 volts per cell:

• 14.8 Volts @ 12 volt system
• 29.6 Volts @ 24 volt system
• 59.2 Volts @ 48 volt system


When you notice your controller indicates the batteries are fully charge or current has tapered down, take a hydrometer reading and see what the SOC is. If it is low, you need to raise your voltage. If it is high you should notice gassing and need to lower the voltage. Repeat as often as necessary until you find the sweet spot. Do not be surprised if you cannot reach 100% SOC. That would mean you panel wattage is too low and you will need to be using your generator more frequently. Don’t EQ the batteries to frequently. If you are not able to get to 100% bring them up with a generator about every 2 or 3 weeks. Just don’t let the batteries get below 50%.

Once you have found the sweet spot don’t completely relax, because it will not last. Seasonal and even monthly changes will be required because the Sun Hours change from week to week. What worked last week may not work next week. Basically in warmer months you will be running lower voltages than cold months. In cold months you will be running higher voltages than warm months. Don’t fear because you should be performing weekly Preventive Maintenance which checking Specific Gravity with your new Hydrometer. Did I mention you need a Temperature Correct Hydrometer?
Thanks to Sunking.
6 x JA Solar 320w solar panels facing NW, 4 x 300w panels facing North.
12 x 2volt Narada lead carbon batteries (24v 400ah), Classic and WBJr, Epever 50A controller, Outback FX2024 inverter and Mate, Trimetric monitor, Alibaba solar pump.

Westbranch

Is he correct?  Simplified answer=== Partially.

I will not get into correcting all the obnoxious statements that he spewed.out the

It is my opinion that 99% of the active members here know all about the Commercial/Industrial chargers Industry uses and the incompatibility (unachievable without Grid or Generator ) to Solar based charging , regardless of the brand

KID FW1811 560W >C&D 24V 900Ah AGM
CL150 29032 FW V.2126-NW2097-GP2133 175A E-Panel WBjr, 3Px4s 140W > 24V 900Ah AGM,
2 Cisco WRT54GL i/c DD-WRT Rtr, NetGr DS104Hub
Cotek ST1500 Inv  want a 24V  ROSIE Inverter
OmniCharge3024  Eu1/2/3000iGens
West Chilcotin 1680+W to come

asdex

Thanks for your reply.
Being in the 1% do you think I should reset my classic voltages to that metioned in the text given that for the last six months my classic reaches 100% SOC but just checking with a hydrometer yesterday the reading was 1150?
Thanks,
6 x JA Solar 320w solar panels facing NW, 4 x 300w panels facing North.
12 x 2volt Narada lead carbon batteries (24v 400ah), Classic and WBJr, Epever 50A controller, Outback FX2024 inverter and Mate, Trimetric monitor, Alibaba solar pump.

Westbranch

#3
WEll, change to me is misleading... You do not want to make changes to all the variables you can , in one massive adjustment ... doing so will result in you not knowing what worked and whar did not.

  first, how do your settings doing the summer period? Float every day? SG in the recommended range? Probably are...

Next is to compare your Bulk/ Absorb Voltage to the recommended  higher(est) voltage from your Batt. maker.

Do/did you lengthen the Absorb time limit?, it needs to be much longer (like 2X or more) in the winter than in the summer. depending on just where you are situated.

Is your End Amps value in the lower part of the recommended range 1 - 3% ? A lower EA value also extends the Absorb time..

In essence, a longer Absorb will probably be ended when the sun drop over the horizon...

This should get you started...

ps, I use 2 sets of settings,  one for summer and one for winter

hth
KID FW1811 560W >C&D 24V 900Ah AGM
CL150 29032 FW V.2126-NW2097-GP2133 175A E-Panel WBjr, 3Px4s 140W > 24V 900Ah AGM,
2 Cisco WRT54GL i/c DD-WRT Rtr, NetGr DS104Hub
Cotek ST1500 Inv  want a 24V  ROSIE Inverter
OmniCharge3024  Eu1/2/3000iGens
West Chilcotin 1680+W to come

asdex

The battery normally float every day summer and winter. Occasionally in winter we miss float for a day or two. Not often. I haven't used a hydrometer until now instead going by the Classic and Wizzbang figures.(my mistake it seems). I haven't programmed ending amps. I haven't adjusted absorb time which is two hours. Voltages are at manufacturer values of absorb 29 volts and float 27 volts.
6 x JA Solar 320w solar panels facing NW, 4 x 300w panels facing North.
12 x 2volt Narada lead carbon batteries (24v 400ah), Classic and WBJr, Epever 50A controller, Outback FX2024 inverter and Mate, Trimetric monitor, Alibaba solar pump.

Westbranch

I looked for the charge specs and could not find anything for solar .... then I was looked for the Solar charging specs  and this thread came up and is almost identical to your issue... nothing seems to have changed since then...

http://forum.solar-electric.com/discussion/21837/crown-cr430-charging-recommendations

hth
KID FW1811 560W >C&D 24V 900Ah AGM
CL150 29032 FW V.2126-NW2097-GP2133 175A E-Panel WBjr, 3Px4s 140W > 24V 900Ah AGM,
2 Cisco WRT54GL i/c DD-WRT Rtr, NetGr DS104Hub
Cotek ST1500 Inv  want a 24V  ROSIE Inverter
OmniCharge3024  Eu1/2/3000iGens
West Chilcotin 1680+W to come

Ron Swanson

I didn't read the whole rant but it sounds pretty much what we have been doing.

Set all voltages at the highest end the battery manufacturer allows and extend absorb time to 2-3 hours.  Not exceeding maximum current acceptance of the batteries of course.

Every situation is unique.  Different array sizes, different shading and times of day.  If they use too much water something will need to be backed off and if they don't reach proper SpG then they need more of something, balancing generator run times and such.

We tell people to look at it as generator and batteries with a solar bonus when available.  Some run summer without generators but few get very far when the angle gets low and the clouds roll in.

asdex

Thanks very much for the information. Soon as we get some sun I'll make some changes.
Cheers,
6 x JA Solar 320w solar panels facing NW, 4 x 300w panels facing North.
12 x 2volt Narada lead carbon batteries (24v 400ah), Classic and WBJr, Epever 50A controller, Outback FX2024 inverter and Mate, Trimetric monitor, Alibaba solar pump.

ClassicCrazy

I think the standard recommendation on these forums is for people to study their batteries when they get them and monitor the current and SG while also using and tweaking SOC to get a good setting for the Ending amps. 

My understanding of the voltage range for batteries would be to start with the lower part of the range and raise it as needed as the batteries age.   

My battery supplier says heat is the worst thing for batteries longevity so keeping them cool - air space between the cells if possible helps.

I also did not try to digest that long blurb but it seems more intended for people who undersize their PV and discharge their batteries too far , especially in the winter when day length is reduced.

Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

Vic

#9
Hi asdex,

Agree with Larry,   that this seems to assume that folks usually undersize PVs.

The post that you copied may have been old.   This situation was more common,   five,  or more years ago,   when PVs were expensive,   and batteries,  less-so.

The standard recommendation  is to follow what the battery manufacturer suggests.  If the battery manufacturer does not provide charger settings for solar-charges systems,  then ask them for those.

This battery manual included RE (Renewable  Energy)  charging settings:
https://www.solar-electric.com/lib/wind-sun/Crown-Deep-Cycle-Product-Support-Broch.pdf

For off-grid systems it is very important to monitor battery condition frequently.   For off-grid Flooded battery systems   use your Hydrometer to measure the actual SG of the battery bank once per month (or so) when you believe that the batts are fully-charged.   Record these readings in the Battery Log Book (number/letter batteries/cells with felt-tip pen).

Among the cells with the lowest SGs from those readings,   choose at least one Pilot Cell per string of batteries,   and use those for a quick read on the nominal SOC of the battery bank.

RINSE,   RINSE ...   AND RINSE AGAIN,    the Hydrometer after each measuring session,  to preserve the accuracy of the Hydrometer.

Any battery Monitoring device will ONLY give approximations of the SOC of the battery,  even when battery parameters are entered into such devices.   The greater number of days since a REAL full charge on the battery,   generally,  the less accurate will be the SOC reading on any battery monitoring device,  including those from the WBjr/Classic combo.

Recall that you are in NZ,   so,  your solar days should not be too short,   depending upon shading,   PV elevation angles/azimuth,   etc  ...

At  SGs of about 1150,   the battery is at a fairly low SOC.   You should not worry about changing the Absorb voltage,  And the Absorb time  NOW.   Would suggest about 30 - 30.5 Vabs for now,  and about 6 - 7 hours Absorb time.

When  the battery gets as fully charged as possible,   you should EQ  at the high range of recommended Veq.   Of course monitor the battery temperature (you are using the Classic's  BTS,   aren't you?) during EQ,   and stop the EQ,   before reaching a battery temperature of about 40 degrees C.

More Later  --  bottom line,   get those batteries charged NOW.   If you need to run your generator,   and have a good charger,   use it.

FWIW,   Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

asdex

#10
Hi Vic, thank for your advice. I am charging them up with my generator today. I can do this via my Outback inverter but will compare it with my 24 volt battery charger.
One thing I notice is although the batteries are showing 1175 on the hydrometer, the Classic SOC is 100% so seems to be reducing charging to the batteries.
How can I change the SOC so its more accurate?
Thanks,

PS, the voltages in the PDF you mention are what I have been using for the last year and everything looked good until I tested with a hydrometer and found the batteries to be 1150.
6 x JA Solar 320w solar panels facing NW, 4 x 300w panels facing North.
12 x 2volt Narada lead carbon batteries (24v 400ah), Classic and WBJr, Epever 50A controller, Outback FX2024 inverter and Mate, Trimetric monitor, Alibaba solar pump.

ClassicCrazy

You can adjust the SOC with the efficiency and capacity in the Whizbang setup  . Also make sure you have the temp set correctly in there according to your battery manufacturer .

Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

Vic

#12
Hi asdex    (is your name Al?),

Regarding the Setup of the WBjr,   several things;

As Larry noted  you should have the battery Reference Temperature set to the reference point used by Crown.   This would generally be 25 C.   Some battery manufacturers use 27 C.

You will usually want the SOC to reset to 100% when the Classic transitions to Float (on its own).   From the WBjr Manual,   
"   ...   The Net Amp-hours tally can be configured to reset every time the Classic goes to float. To set this option, go to the “TWEAKS” menu and press “MORE” four times. Select “WBRST” and press the UP or DOWN arrow keys to select “YES.” Press Enter to save. “NO” (or no reset) is the default  ...   ".

You probably have that set correctly.

One of the most important WB parameters,   is to set the battery CHarge Efficiency  to a good starting point for your Flooded batteries.   The Ah efficiency of healthy new Flooded batteries (FLAs),   is about 85%.   This value  will tend to diminish,   as FLA batteries age.  If you have set this number in the 90s,     as the manual suggests,   this  might part of the SOC  reading inaccuracy shown by the Classic.

And,   again,   if your Vabs and Absorb time are not set to generally fully-charge the battery bank,   when the Classic goes to Float,   and the Classic is set to show 100% SOC  at that point,   then,   this number could be quite erroneous,   showing 100%  SOC,  when the battery is  far from that.

Please ignore the stated SOC,  until you get the battery bank fully-charged.   Then,   after confirming the WB Set-up parameters,  you can try to adjust the SOC number closer to the reality of the battery SOC.

FWIW, Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

asdex

Thanks, I have reset the efficiency from 95% to 85%  and checked the reset which is correct. The battery temp comp is 20 deg C and 0.1%. I have set absorb to 30 volts for now but SG is still low at 1175 as we have had no sun the last two days. I have a 6.5kva generator and 25amp 24 volt battery charger which I have been using but the charger only charges the bank at about 7 amps. This is when set to boost. Not sure why the charge current is being limited by the batteries.
I have set ending amps to 2 and ticked " use WBjr for end amps". Rebulk volts??? Is on 8.
Cheers,
Graham
6 x JA Solar 320w solar panels facing NW, 4 x 300w panels facing North.
12 x 2volt Narada lead carbon batteries (24v 400ah), Classic and WBJr, Epever 50A controller, Outback FX2024 inverter and Mate, Trimetric monitor, Alibaba solar pump.

ClassicCrazy

That sounds high for the Absorb voltage and too low for the ending amps. Might be boiling your batteries a lot with those settings.

You may have an automatic battery charger made for vehicles. They taper off the charge as the battery voltage rises - so people don't cook their batteries .

Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable