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Battery gravity doesn’t look good

I can comment on the batteries but i have no little to no experience with asian made electronics, I bought 2 EPsolar Tracers, when they trashed my batteries i disposed of them and bought all high quality controllers and chargers that are fully programmable and do not refer to generic types for setting. I therefore cannot comment on settings for a particular controller, I can tell you what the battery manufacturers state.

The display on the Tracer only shows what is put into the battery and what is taken from the battery from the output terminal of the tracer.....IF YOU HAVE ANY CONNECTIONS DIRECTLY TO THE BATTERY THE TRACER CANNOT “SEE” that current.

A true battery state of charge indicator MUST have a current shunt right at the battery where it can measure TOTAL CURRENT both into the battery and out of the battery......IT must also measure the voltage right at the battery

The original TRUE STATE OF CHARGE monitor is the BOGART ENGINEERING TRI-METRIC, Victron makes one that does this but it only works with a full VICTRON system, if you have equipment from others in the mix the Victron will have non accurate information.

In any case the true state of charge is read by a hydrometer or a refractometer.

WHAT IS PAINFULLY OBVIOUS TO ME.......You do not have a proper charger that is capable of doing a full equalization charge, The charger should not be in eq before the Bulk phase has finished. Go back and do bulk or Adsorb phase until each battery hits its terminal voltage......then move on to e.q. phase

Even though i do have high quality controllers and chargers, i verify the voltage and amperage settings with an external device that is specialized to that purpose, Personally all my meters are FLUKE or others in the same quality range, that can be calibrated by a calibration laboratory to NIST standards. My choice FLUKE 87V NIST......about $500.00, i use several Fluke 77 IV DVOM ($360) as my bench meter but i verify that against the 87V which is verified by a Fluke lab standard.

It is not a simple proposition to simply charge up a battery to recover from a very low s.g. reading. For now only believe your refractometer, they basically cannot go out of calibration unless you smash the device hard enough to not be able to see the scale. Yours has a built in calibration set point with the “water” line at the very bottom. To verify get some good quality distilled water that has very low T.D.S. (total dissolved solids) such as Arrowhead Puritas and check your refractometer with that. it should read 0.0 , the water line on your refractometer, but unless really abused, its fairly impossible for them to be not accurate.

The meter readings in the Tracers are “approximate guesses“ as they are not taken right at the battery terminals , not to be relied on....

For now.....with the units that you do have in possession do keep charging those batteries with no load on them, only use the refractometer and do get, beg, borrow , i cant suggest “steal” a reliable voltmeter and verify the voltage at the Tracer terminals, I think that you will find that the tracer readings are WAG’s......wild assed guesses....
Hello Technodave,
@Simonbr2

Very good, thank you. Now i can tell you that you do not have a dead cell, all cells are within .020 or so .

First off calibrate your spectrometer, very simple, test good quality distilled water, it should be on the water line.

Assuming that your spectrometer is accurate......

This is what is happening.....you are not charging nearly enough for the loads that you have, first thing get some auxillaty power to recharge that pack , keep your loads to a minimum, and apply a steady 40 amps for at least 5 hours, then retest, record results, if s.g. is starting an upward trend, do it again, set the charger to bulk mode, it should stay there. This may well take several days of recovery to see good results.

Do not under any circumstances listen to anyone who says to put epsom salt in a battery.......that is old wife‘s hearsay.
The only thing to add to a Flooded Lead Acid battery is good quality distilled water.....NO not reverse osmosis, OR rainwater, OR filtered water, There are better sellers of distilled water, if in dought go to a major pharmacy and see what they sell.......its widely used in the medical field.....for medical prep, they will not be selling grandamas fififofo water. In California there are Arrowhead Puritas and Calistoga who do it right, anyway, its a bit more expensive.

No dont throw away your investment in those batteries, that is the best lead acid for solar use, you are going to learn that making your own electricity is way more complicated than just buying it from the POCO, if you give up that easily you are in for a nightmare when it comes to lithium, they are technically far more demanding....

Ive said before that i can get more than 20 years on that kind of battery, but that comes with scheduled maintaince. I did state that I have two separate banks of L-16 batteries, one reason is shutdown and service time. I use large marine switches (Blue Seas) to isolate systems for service. You might consider having a backup set. The common GC-2 golf cart battery is built to the same standards as the L-16 traction batteries and will work well is parallel, its not ideal but you should have a standby just in case
Thank you Tecnodave,

My spectrometer is new and came with a small vial of distilled water to be able to calibrate. I did make sure the device was calibrated to 0 before first use.

Currently at my camp the only option I have is my Abso inverter/charger when running my generator, but I believe this is not a proper charge for the batteries I have. It does a 55a charge but I don't know at what voltage (i guess I can check with my multimeter if needed). I can also reduce in the options to 35amp instead of the 55a, but nothing in-between. Does the charge voltage matter? I can always purchase a 40a charger that I can connect to my generator and charge my batteries using this, I just don't know if the voltage matters (i know on the SCC its set to 14.7v).

The batteries I have are 420aH and 10% for the charge is 42 amps, my current load (fridge and RV) is about 7amps at least 30 minutes out of an hour the loads are at the full 7 amp and the other time at least 1 to 2 amps. For this reason I was wondering if it would be better to have a 50amp SCC, this would allow a full 42amps minimum to the battery as well as a little extra for the load being used. I know when the fridge will be idle, it will not need the extra amperage and it will be going to the battery.

I currently have a shunt with a volt/amp meter along with a digital multimeter(Klein Tools MM100).

I had not heart about the salt but I can promise you that I am not putting anything in the batteries other then distilled water (from the pharmacy or the battery store).

I wish I could get a second pair as backup but its not really in my budget, the CG2 pair I was going to purchase is still in the $600 range and its a little much for me.
 
@Simonbr2

The Klein meters are good , they are made in china but Klein is the oldest electrical tool maker in the US, good 50 years older than SnapOn, they wont sell junk.

That is really expensive for GC-2 batteries, I paid $420 for 2 Interstate L-16 but that has been a while.

I dont know anything about Abso, I do not know of them. Any charger should be able to bring up the batteries from where they are.


This one might sail right over your head but read it, then read the solution.....its difficult to understand...

One thing missed when running a battery charger from a generator is power factor, Cheap chargers have a horrible power factor which is when the current leads or lags the voltage, caused by the inductive transformer in the charger.
The result is that the 1000 watt charger needs a 2000 watt generator to handle the power factor.

The solution when running a charger from a generator is to use a “power factor corrected” charger. These will cost more but will deliver near the generators full power to the battery. i.e. 950 watts DC out from 1000 watt generator verses at best 450-500 watts from a 1000 watt generator running at full load. <edit> (with no power factor correction)

Like i said.....a bit hard to understand....you dont get this in basic electricity......

Old school transformer based chargers have a horrible power factor.......modern switch mode chargers are better but still need to be “power factor corrected”

David...
 
@Simonbr2

The Klein meters are good , they are made in china but Klein is the oldest electrical tool maker in the US, good 50 years older than SnapOn, they wont sell junk.

That is really expensive for GC-2 batteries, I paid $420 for 2 Interstate L-16 but that has been a while.

I dont know anything about Abso, I do not know of them. Any charger should be able to bring up the batteries from where they are.


This one might sail right over your head but read it, then read the solution.....its difficult to understand...

One thing missed when running a battery charger from a generator is power factor, Cheap chargers have a horrible power factor which is when the current leads or lags the voltage, caused by the inductive transformer in the charger.
The result is that the 1000 watt charger needs a 2000 watt generator to handle the power factor.

The solution when running a charger from a generator is to use a “power factor corrected” charger. These will cost more but will deliver near the generators full power to the battery. i.e. 950 watts DC out from 1000 watt generator verses at best 450-500 watts from a 1000 watt generator running at full load. <edit> (with no power factor correction)

Like i said.....a bit hard to understand....you dont get this in basic electricity......

Old school transformer based chargers have a horrible power factor.......modern switch mode chargers are better but still need to be “power factor corrected”

David...
The prices I posted are Canadian and I also live in a smaller city so the prices are higher then big city’s.

I do understand what you are saying, I have a Yamaha ef3000is 3000w inverter generator. Don’t have a charger yet but will look around to see what there is available, do you have any suggestions?

what do you of my idea of going to a 50amp SCC instead? Are there any brands that allow you to limit the amperage to the battery?
 
You do need more charge capibility, rather than replacing what you have, another charge controller with its own array should help, but alas i know little about what you have. I do well understand small towns out back, Im from a farming valley where our small town was 50 miles away and the big city.??? was 100 miles away.

I now live in costal California where there are many solar industries. I just bought 200 watt Panasonic multi layer panels at $20. each, used about 7 years into a 20 year guarantee. I cant go wrong at that price.

I cant speak for most controllers but i do beleive that charge current limiting is in most good charge controllers. This feature will allow you to “overpanel” your controller somewhat so you will still get a good charge on a shady to cloudy day. It definitely is available in the Classic and Outback units that i am familiar with.

To start with i would limit overpanelling to 125% of the maximum setting of the controller.

Its kind of a judgement call on that...I live but a few miles from the Pacific Ocean and overpanel my 2400 watt capable 86 amps at 28.8 volts, MidNite Classic 150 controllers with 5000 watt solar arrays when i will have sustained days of foggy drippy wet weather but when the sun reappears from the for i hit those disconnect switches, and cover the unused arrays.....I do have a generator but i'm not into wasting monies.....fuel is expensive

I use secondary controllers to handle excess power that the batteries do not need to water heater elements......diverting directly from the 28.8 volt charge current through a diversion controller (Trace C-40) to 24 volt heating elements
 
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You do need more charge capibility, rather than replacing what you have, another charge controller with its own array should help, but alas i know little about what you have. I do well understand small towns out back, Im from a farming valley where our small town was 50 miles away and the big city.??? was 100 miles away.

I now live in costal California where there are many solar industries. I just bought 200 watt Panasonic multi layer panels at $20. each, used about 7 years into a 20 year guarantee. I cant go wrong at that price.

I cant speak for most controllers but i do beleive that charge current limiting is in most good charge controllers. This feature will allow you to “overpanel” your controller somewhat so you will still get a good charge on a shady to cloudy day. It definitely is available in the Classic and Outback units that i am familiar with.

To start with i would limit overpanelling to 125% of the maximum setting of the controller.

Its kind of a judgement call on that...I live but a few miles from the Pacific Ocean and overpanel my 2400 watt capable 86 amps at 28.8 volts, MidNite Classic 150 controllers with 5000 watt solar arrays when i will have sustained days of foggy drippy wet weather but when the sun reappears from the for i hit those disconnect switches, and cover the unused arrays.....I do have a generator but i'm not into wasting monies.....fuel is expensive

I use secondary controllers to handle excess power that the batteries do not need to water heater elements......diverting directly from the 28.8 volt charge current through a diversion controller (Trace C-40) to 24 volt heating elements
This setup seems much more complicated then what I want to get into, we camp from may to October, mostly weekend and maybe half of July (holidays). The main items I power are a dc fridge at about 6 amps then the camper rv, anywhere from 1 to 5 amps here and there. So far the L16 interstate work but when looking at SG they are not doing well. US batteries data sheets shows to charge them 10% which is 42a for the 420ah.

currently I have 2x 350w panels, my SCC is only good for charging at 40a (520w) max and pv 780w (92v).

This is the reason I believe going to a 50a SCC will be better for me. First off I will be able to add a third 350w panel, giving more power even on cloudy days. Second, allowing me to charge at the full 42a while giving me about 8amps for “other” loads during the day. What’s the harm in 8a over recommended charge rate rather then being under almost at all times?

today was a sunny day and my batteries charged and the SCC shows that the batteries were full but my SG still only showed 1.13. I didn't see the voltage reach the 14.7 i set for boost either and I was not able to push the 40 amps to the batteries because my other loads. This is very frustrating.

how exactly does the SG have in relation to the charge of a battery? I want to make sure I understand correctly. The way I understand, the charge is held within the acid mixture, so if the acid is not mixed up well within the cells, the charge that is held will be shorter then if the acid was well mixed.
 
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Ok, now that i kinda know what you have, yes do upgrade to a 50 amp unit. It wont hurt the battery to charge at 50-55 amps while still in the bulk phase, That is better than running so low a s.g.. Your impression that the energy is stored in the acid is not correct. The energy is stored in the positive and negative plates in the battery which change chemical composition on charge and discharge. The transfer is accomplished through the acid which does change along with the state of charge.

One big point with Flooded Lead Acid that you are missing. You cannot use the full amount of energy stored in the battery and get long life out of them. For best life of FLA keep the state of charge between 50% and 100%. So you really have a useable capacity of 210 amp hour from your set for long life.

I switch to my backup set when my state of charge hits 60%.....

One point that is really missed is series / parallel connections of the panels. For a 12 volt system keep all the panels in parallel so the controller doesn't have a huge conversion ratio from the P.V. voltage to the battery voltage. I see many folks wiring up panels to the maximum capability of the controller i.e. 150 volts then converting that to 14 volts at the battery.......that is a 10 to 1 conversion ratio.....that taxes the controller, making it work harder and less efficient. the result is that the controller gets hotter as it is less efficient at high conversion ratios, the result is less power output to the batteries and more power lost in heating up the controller.

Using the very same panels and controllers with all parallel wiring will result in a conversion ratio nearer to 3 to 1 which is way easier on the controller as less power is lost in the conversion ratio. AND that lost power is converted to heat in the controller.

The ideal power conversion ratio is somewhere between 2.3 to 1 and 3.5 to 1. example 33-43 volts in for a 12 volt system. Some controllers will work at 1.3 ratio (Victron) but again efficiency suffers.

As i have 6 big controllers and hundreds of panels to test with I have done side by side testing in this area, Using two identical controllers and panels and using array of 2 series 6 parallel (70 volts) verses 3 series 4 parallel (105 volts) (on a 24 volt system) and found a startling difference in power generated but more startling was the difference in temperatures recorded at the controllers

I was seeing 195 degrees on one of my high conversion ratio controllers.

Let me put that in comparsion......If you had a really high quality stereo power amplifier and put that in an oven and run it at full power it will not last too long.......but in the quiet corner with cool air it will last far longer and sound better in the cool air....


So if you are using typical grid tie panels (the most cost effective) at 60 cell, approx 30ish volts all panels should be in parallel for 12 volt system, in series strings of 2 (60 volts) for 24 volt systems, and series strings of 3 (90 volts) for 48 volt systems.

There is one character on YouTube who has purchased MidNite Classic 250 controllers and is running them at 245 volts in and 14.7 volts out a whopping 16.667 ratio. He has glued a huge heat sink to the back of each one and runs them at 240 degrees where they do a self protective thermal shutdown and he whines that the controllers are no good.....LOL....A fool wasting money and energy

You can tell all the people something but many have their ears glued shut and cannot waver from what they know, just cant learn. they will be stuck in the past forever....

Stick with it, you are a learner, you will go far.....
 
I cant speak for most controllers but i do beleive that charge current limiting is in most good charge controllers. This feature will allow you to “overpanel” your controller somewhat so you will still get a good charge on a shady to cloudy day. It definitely is available in the Classic and Outback units that i am familiar with.

Even better, rather than regulating DC current delivered to battery + inverter (battery only gets what inverter doesn't want), is to regulate battery charge current.

Victron charge controller, battery shunt, and monitoring device accomplishes that by commanding charge controller to maintain target battery current.
The same can be accomplished in AC coupled systems, and hybrids.
It is just dumb separate SCC and inverters which don't.

FLA prefers a specific constant current during bulk charging.
 
Even better, rather than regulating DC current delivered to battery + inverter (battery only gets what inverter doesn't want), is to regulate battery charge current.

Victron charge controller, battery shunt, and monitoring device accomplishes that by commanding charge controller to maintain target battery current.
The same can be accomplished in AC coupled systems, and hybrids.
It is just dumb separate SCC and inverters which don't.

FLA prefers a specific constant current during bulk charging.
After reading and monitoring the current change using my battery meter shunt device, I was starting to think the same thing. Can Epever MPPT sense by resistance or something if the batteries are getting the correct amount of amps? I currently have the Epever 40a MPPT and the 50a version on its way. At first I thought that the SCC was maybe sensing the resistance or something while it was charging the battery but I don't think the SCC is that smart. My load is always between a minimum of 3ish amps and 10 amps, sometimes more, and the battery is never getting the full 40a (10% of 420ah).

For this reason I was looking at the Midnite classic with the whizbang jr to be able to sense what is actually going into the battery so that I get a proper bulk charge with the correct current. Now that you mention that the Victron also has this technology I will for sure take a look at that unit also.

I was wondering if I had to increase my charging amperage if I add another battery to my setup? I currently have 2x 6v L16 Interstate at 420ah. I wanted to double to increase my ah so i could get the full 420ah. The US Batteries data sheet (what people are saying the batteries are) states that the charge current should be 10% of the ah, so in my case 42 amps. If adding a second bank of 6v, do I now have to charge with 84amps?
 
I don't think Epever has a pair of sense leads for an external battery shunt. What it should do is deliver up to its rated output current (or max set charging voltage.) It should act like a CC/CV power supply until it decides to switch to float.

(When people top balance lithium cells with a bench supply, if the wires and alligator clips have high resistance, supply regulates voltage at its end but due to IR drop batteries see lower voltage. Supply sits in CV mode and batteries with lower voltage applied draw low current. It gets there eventually, just slow.)

I saw that Midnight has WhizBang Jr shunt (with some electronics) but I don't know what they do with the information. I thought it should be able to control SCC so battery current is regulated, but I haven't read that in their instructions.

Midnight has an additional box which connects to the shunt and sends commands to SCC.

If you have FLA, there will be a preferred current to keep electrolyte stirred by bubbling.
You have 2x 6V = 12V at 420Ah. Assuming 50% DoD you can use 210Ah. You want to connect two more batteries 2s2p for 12V at 840 Ah so you can drain 50% = 420 Ah?
Yes, should double charge current. What is preferred current? maybe 0.12C, 50A? With two in parallel then you would want 100A.
Also, review battery manual find the exact absorption and float voltages recommended, program your SCC for that if it is adjustable.
Use a battery temperature probe so SCC can adjust voltage with temperature.
 
I don't think Epever has a pair of sense leads for an external battery shunt. What it should do is deliver up to its rated output current (or max set charging voltage.) It should act like a CC/CV power supply until it decides to switch to float.

(When people top balance lithium cells with a bench supply, if the wires and alligator clips have high resistance, supply regulates voltage at its end but due to IR drop batteries see lower voltage. Supply sits in CV mode and batteries with lower voltage applied draw low current. It gets there eventually, just slow.)

I saw that Midnight has WhizBang Jr shunt (with some electronics) but I don't know what they do with the information. I thought it should be able to control SCC so battery current is regulated, but I haven't read that in their instructions.

Midnight has an additional box which connects to the shunt and sends commands to SCC.

If you have FLA, there will be a preferred current to keep electrolyte stirred by bubbling.
You have 2x 6V = 12V at 420Ah. Assuming 50% DoD you can use 210Ah. You want to connect two more batteries 2s2p for 12V at 840 Ah so you can drain 50% = 420 Ah?
Yes, should double charge current. What is preferred current? maybe 0.12C, 50A? With two in parallel then you would want 100A.
Also, review battery manual find the exact absorption and float voltages recommended, program your SCC for that if it is adjustable.
Use a battery temperature probe so SCC can adjust voltage with temperature.
Yes my batteries are FLA. I’ve already set the SCC to the manual specs (bulk 10% of 420ah, 42 amps, boost 14.7v, eq 15.3v, float 13v). The temp probe is taped to center side of battery.

currently I have 4 solar panels (350w x 4) connected in 2 pairs seried then paralleled, where I have it installed it’s not easy to get sun for a large part of the day, so I Installed 2 series in one location and 2 others in another location.
 
Even better, rather than regulating DC current delivered to battery + inverter (battery only gets what inverter doesn't want), is to regulate battery charge current.

Victron charge controller, battery shunt, and monitoring device accomplishes that by commanding charge controller to maintain target battery current.
The same can be accomplished in AC coupled systems, and hybrids.
It is just dumb separate SCC and inverters which don't.

FLA prefers a specific constant current during bulk charging.
What shunt is needed to perform proper battery current charge in the victron? Is the monitoring device needed or is that the smart phone connected to Bluetooth for setup
 
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