Boiling Mad

Sakamochi · September 2017

System:

Location: Northeastern AZ 5500 ft elevation. Full sun exposure 6 am to 7 pm midsummer.

48 volt system 16 Interstate L16 new in 7/2014 with water miser caps in Battery box with Auto exhaust

MX-60 Charge Conroller

Xantrex 5500(?) Inverter Charger

16 Kyocera 140 watt with Wattsun Tracker

900W Wind Generator

12 kw Kohler Propane Auto Backup Gen installed Dec 2015. It has come on automatically twice in this time due to low battery voltage. Batteries are in perfect condition 99% of the time.

The controller, wind gen, inverter are all original equipment 2007. The home is occupied 1/3 of the year. The power usage occupied is 5 kw per day, away is 2.3 kw per day. Generator has been used twice by auto on feature meaning thatthe batteries are 99.9 OK all the time.

FYI I am a retired electronics engineer. I take care of my system like it was my first born, always super maintained. I check SG, battery individual voltages at night, etc.

Problem #1: February 2011 original Trojan L-16s failed catastrophically due to boil out, Service company said the Trojans failer all over and they were junk after making some construction change in 2006. Thet were replaced with Rolls 400(?) @ $6,000

Problem #2: Rolls began to have some batteries with low SG after about one year. I tried making a claim which went largely nowhere even though I keep records of SG, temps, usage etc. The rest had some catastrophic failures (not all about half) in July 2014. Different sevice company found that 25% of my panels were disconnected internally due to water leakage in a junction box and corroded open leaving 75% power. I thought that probably explained A) why my power output was only getting to 1500 watts and why the batteries may have failed in the end. There was no auto backup gen in that time period, however, power never went down then either.

Replaced Rolls with Interstate L-16 in July 2014, Different Service company replaced the batteries, found the panel problem and fixed that. The Outback Watt power jumped to 2490 watts in November 2016 with current at 46.2 amps (53.9 vdc in bulk charge mode). I managed a manual Equalize that month with no issue. In June July 2017 it still cannot get past 1750 watts in hot weather.

We believe now that during equalization in the hot months our sixteen 140 watt rated solar panels cannot get to full power due to temperature de-rating. Checking the Outback output watt meter it gets to about 1750 watts at best in high temps (July Aug 100 degrees ambient). The Equalize setpoint is 60.4Vdc @ max current, so the "Outback" charge controller simply keeps on trying and goes as high as it can (59.1 Vdc) and hangs there. This output is just above the absorb setpoint (which it has no problem with). There is no Equalize time limit function if it never gets to the Equalize voltage setpoint. The Outback repeats an Equalize function day after day until the Equalize cycle of three hours is satisfied (which it never can get to then). It keeps boiling the batteries. I determined this by noting that the power output on the Outback can only get to 1,720 watts (59 volts @ 30 amps) while trying to equalize. In cold months it can get to 2400 watts, so there is no problem getting 60.2 Vdc at 40 amps in cold weather. It simply does not produce enough power to raise the voltage high enough at the current needed for equalization when it is hot. I have investigated extensively and no one, including two installer companies ever heard of this issue. I had replaced the caps on my new batteries with Water Miser caps due to excessive water loss (spitting up on the tops), although I had no idea why this happened so much especially in the hot months. I had serviced the batteries on July 29th 2017 and all the cells were full of distilled water at that time. I was away from July 29th and did not return until Sept 6th (a broken rib ouch) only to catch the system stuck in Equalize mode which it was programmed to start on August 25th. I determined that it had been in Equalize for 11 days straight (the last float day was 11 days before that, and it is ALWAYS in float every day unless it is cloudy). I was fortunate to catch it when I did, as some of the plates were just slightly exposed (1/16 inch maybe and sill wet), the thermocouple between the batteries read 124 degrees F (ambient temperature was 98 degrees). There was NO WATER on the exterior of the batteries. The Water Miser caps probably saved me $6,000. If factory caps were on the batteries there would have probably boiled out after only a couple of days much as my previous set of Rolls batteries had, having their "factory caps". My "new" batteries seem to have recovered and seem to be OK today with SG variance about 25 points on two battery cells, 5-10 on the rest and all the night time voltages are 6.37 +/- 55 mv (not in float mode).

Questions:

1) Is my theory correct? Is solar panel voltage limitation causing the equalize hang up?

2) Setting see below: do these look right to you?

3) I never tried to use the generator to Equalize. I am sure that it could if the settings were correct...?

3) I turned off my Outback Auto Equalize (a little late if my theory is correct) and will manually equalize in the winter only.

4) Two of my batteries on the end row have little black specks floating up in the SG bulb. What to make of that?

Thank you Experts for any help!

Clem (Sakamochi) also email me Campmaster@cox.net if you would like to

		Voltage Set Points
per	Bulk	Absorb 2 hrs	Float	Equalize 3 hrs
MX60 actual original 2007 set point	--------------	57.6	54.4	60.2
MX60 Manual reccommendation	--------------	59.2	53.6	57.6



Roll Service Answer (old battery set #2)		59.2	52.8	61.92


Specific Gravity	Full Charge			1.265


New Interstate Batteries 7/9/2014		58.4	53.2	60.4

MichaelK · September 2017

How are your panels wired? Are they 4 arrays of 4 panels in series (4S4P)? If these are the 17.7V Kyocera panels, your charging voltage would be only 70.8 volts, which seems too low for a 48V system. You have your L16 batteries wired as two parallel banks of eight batteries? If they are 370 amphours like my Trojan L16s, they need at least C/12, which in your case would be (370/12) X (2 banks)= 61.7 amps. I charge my Trojans at 59.3 volts, and I would expect you to need >3600 watts to get to a minimum of C/12.

One short-term thing you can do is re-wire your panels to increase the input voltage. You could try a 5S3P configuration, or buy two additional panels to get a 6S3P configuration. With 6 panels in series, you'd get ~106 VDC, with the Voc approaching 150V only at about zero F.

To itemize:
1) Too low wattage for that size bank
2) Too low array voltage to charge under the hottest conditions.

Estragon · September 2017

Do you have a remote temperature sensor attached to the batteries and the controller? If so, where and how is it attached to the batteries, and have you confirmed that the controller is adjusting voltages properly?

To your specific questions:
1. Yes, it's possible. As an EE you know there are lots of variables - temps of panel surface vs battery electrolyte, gauge and lengths of wire in various segments of the circuit, etc.
2. I have interstate L16s, and the numbers look about right for a base, but actual voltages would depend on temp.
3. I never auto-equalize, there's just too much to go wrong, and IMHO needs human judgement for when to do it, how, and when to stop.
4. I wouldn't get all that worked up about a bit of crud. Drying out the top of the plates wouldn't have done the batteries any good, but probably recoverable. Be sure to rinse the hydrometer though, as you don't want the crud to get stuck.

I also wonder about the balance of system, but the immediate concern to me seems to be the charging itself. I don't think a properly temp compensated controller should be boiling batteries.

westbranch · September 2017

I am wondering why you want to do so much EQ'ing?
EQ as I understand it is used to balance an unbalanced set of cells (battery) and should be monitored constantly over the EQ time line ....

Photowhit · September 2017

I think you have had replies that address 2 of my main concerns.

I don't see a panel configuration that will work with 16 panels. Since it's a 2007 or earlier model Outback charge controller. We have heard directly from the designer that they need to have 30% more input voltage than Output, so at 58 volts you would want 75 volts input. I think they do function below this but not well.

If your batteries are in the Arizona heat, they will have a limited life span, a Battery temperature sensor is imperative. I encourage auto equalizing, but not if someone isn't monitoring the water levels. I also turn mine off during the summer months and pick and choose when I equalize. Even if you have a battery temperature sensor attached it may be shutting down your equalizing as the battery reaches unsafe temperatures. It will also compensate for the temperature of the battery. Lower voltages are needed as the battery warms up, it's an electro-chemical reaction, so heat speeds things up.

Your panels likely put out much less energy than you think! Here is a current Kyocera 140 watt panel specs;

Please note the second set of numbers, these are the Normal Operating Cell Temperature values. In normal heat they can be expected to produce only 101 watts and 16 volts. I would be surprised if you ever saw more than 1600 watts during the heat of summer. This doesn't have much to do with your controller it's just what the panels are producing in the heat. I would think anything over 1600 watts is an edge cloud event. You would likely want strings of 6 for the MX60 to work well.

Your battery bank at 680 amp hours, would like a minimum charging current of 68 amps or 10% of the capacity. Your panels are likely to produce 1600/58= @28 amps. You are in a primarily sunny area and I am discounting your wind generator, more about that later.

Things you might consider are to correct your array configuration and increase your array size, I'm willing to say in a particularly sunny area you can get by with a bit less array, but I would shoot for adding 50% more array, it happens that 24 panels in 4 strings of 6 work for this.

You might consider building a berm shelter for your battery bank, I know the ground is hot on the surface, but if you can get down (or build up) 4 feet you should find some temperature nearer the 70's.

I don't know how reliable your wind generator is? ...or what it is hooked up to? Hopefully another charge controller as it needs a dispersion load or it could be your problem! Wind generator can't be 'turned off' their energy must go somewhere. So this needs it's own charge controller and a dispersion load so that the energy can go somewhere. the charge controller will send it there when the battery bank doesn't need the energy.

mcgivor · September 2017

After reading your original post, along with the replies so far, it would appear there are multiple factors which perhaps independently may go unnoticed however in combination, they manifest into an undesirable situation.
Array output under normal temperatures may be acceptable to satisfy the needs of the battery, in terms of charging, equalization and so forth, but when temperatures rise things begin to change, the system is too close to the fine line in terms of array voltage output versus the requirements needed by the controller to perform it's tasks.
One detail missing is loads during EQ, the loads combined with temperature and the array configuration, may in combination, be the issues worth looking into.

mvas · September 2017

If you are on-site for only 4 months per year, then what if you put the Battery Bank on FLOAT for the other 8 months?
Or, at least, turn OFF EQ !
Does the battery bank actually supply any power to any device / appliance while you are gone?
Do Bulk, Absorb & EQ only when on-site?

petertearai · September 2017

i would be not a big fan of eq when not there . If set to auto eq i would keep the eq time short . Correct me if wrong , but if the eq time is not achieved on the day it is initiated , then it tries to carry on with the next day .

Sakamochi · September 2017

TWO DIFFERENT SOLAR COMPANIES NEVER SAID THIS SYSTEM WAS UNDERPOWERED, MAL-DESIGNED. IT WAS INSTALLED BY COMPANY “A” WHO WENT OUT OF BUSINESS. COMPANY B HAS BEEN AROUND FOR ABOUT 20 YEARS, AND THE OWNER CAME OUT TO INSPECT THE SYSTEM WHEN THE PROBLEM WITH THE ROLLS HAPPENED IN JULY 2014 AND HE PUT IN THE INTERSTATES. I WONDERED BACK THEN IF I NEEDED MORE PANELS…..

IF SOMEONE CAN GIVE ME AN INSTRUCTION OF HOW MANY PANELS OF WHAT KIND AND HOW TO CONNECT THEM TO RESOLVE THE PROBLEM THAT WOULD BE EXCELLENT!

MY RESPONSES ARE IN ALL CAPS:

How are your panels wired? Are they 4 arrays of 4 panels in series (4S4P)?

YES

You have your L16 batteries wired as two parallel banks of eight batteries?

YES

If they are 370 amphours like my Trojan L16s, they need at least C/12,

I DO NOT KNOW WHAT “C12” IS

With 6 panels in series, you'd get ~106 VDC, with the Voc approaching 150V only at about zero F.

I AM A LITTLE CONFUSED ABOUT 106 VOLTS INTO A 48 VOLT ARRAY. IT GETS DOWN TO BELOW ZERO HERE. I CAN ADD PANELS, BUT THEY WOULD HAVE TO BE PUT ON THE UTILITY SHED BECAUSE NO MORE FIT ON THE ARRAY TRACKER.

I EQUALIZED ABOUT TWICE TO THREE TIMES A YEAR, DO YOU THINK THAT IS TOO OFTEN?

I AM ALWAYS THERE FOR EQUALIZE IN THE LAST THREE YEARS EXCEPT THIS LAST TIME WHEN I BROKE RIB AND COULD NOT. LUCKY GOT THERE WHEN I DID.

September 12 #5

I think you have had replies that address 2 of my main concerns.

I don't see a panel configuration that will work with 16 panels.

THE OUTBACK AND THE XANTREX HAVE T/C INBETWEEN BATTERIES IN THE MIDDLE OF THE PACK. THE OUTBACK HAS ITS PROGRAM ON TO REDUCE VOLTAGE WITH HEAT DURING CHARGE.

THE OUTBACK MANUAL STATES THAT THE TEMPERATURE CONTROL IS SWITCHED OFF DURING EQUALIZE, SO THAT IS HOW YOU GET TO 124 DEGREES.

Your panels likely put out much less energy than you think! Here is a current Kyocera 140 watt panel specs;
YOU ARE ABSOLUTELY CORRECT!

consider are to correct I would shoot for adding 50% more array, it happens that 24 panels in 4 strings of 6 work for this.

HOW WOULD I ADD 8 PANELS TO MY SHED AND CONNECT THEM TO THE BATTERIES IN THE SHED? THE ARRAY COMES INTO THE SHED AS 4 PARALLEL 4 PANEL SETS IN SERIES OF 48 VOLTS WITH TWO WIRES. REWIRING OVER THERE AND BRINGING WIRES OVER HERE BACK AND FORTH DOESN’T SOUND LIKE A GOOD OPTION WITH A MOVING ARRAY THAT SWINGS 220 DEGREES.

You might consider building a berm....

THE SHED BATTERY BOX IS A FOOT OFF OF THE CONCRETE FLOOR WITH POWERED AUTOMATIC VENTILATION. THE TEMPS AMBIENT OUTSIDE ARE MAX 106F FOR A COUPLE DAYS IN SUMMER AND 70 OR 60 AT NIGHT. WINTERS ARE 40 F TO -20 DEGREES. I HAVE A WEATHER STATION SO THOSE ARE FACTS.

THE WIND GEN IS AN OLD SOUTHWEST WITH ITS OWN CHARGE CONTROLLER, IT DUMPS EXCESS POWER INTO A RESISTIVE LOAD IF IT NEEDS TO. IT DOES A GREAT JOB.

September 12 #6

One detail missing is loads during EQ,

THE LOAD IS MAX 3 AMPS AC DURING EQUALIZE.

September 12 edited September 12 #7

If you are on-site for only 4 months per year

I TURNED OFF AUTO EQUALIZE LAST WEEK

Does the battery bank actually supply any power to any device / appliance while you are gone?

THE LOAD IS MAX 3 AMPS AC DURING EQUALIZE.

Do Bulk, Absorb & EQ only when on-site?

UNSURE OF THE MEANING OF THAT QUESTION. THE SYSTEM CHARGES BULK, ABSORB AND FLOAT IF IT CAN GET THERE EVERY SINGLE DAY.

Sakamochi · September 2017

One more clarification: I am on site every month for about 2 weeks, so total time is about four months a year, not 4 months all at once. I take care of those batteries every single month.

mvas · September 2017

Sakamochi said:

TWO DIFFERENT SOLAR COMPANIES NEVER SAID THIS SYSTEM WAS UNDERPOWERED, MAL-DESIGNED.

Those two companies "Did not say anything was wrong" because they did not do any research (math).

When the PV Panels are HOT then the PV voltage drops and Max Power drops.
Clearly, you do not have enough PV Voltage when the PV Panels are HOT - ( ie stuck in EQ mode forever )
PLUS, you need some "Head Room" between the PV Voltage and the Battery Terminal Voltage.
What is the MINIMUM Voltage that your PV Panels must produce to support 3 HOURS of EQ?

On the flip side ...
When the panels are cold the PV Voltage will rise.
Now, you have to make sure your Voc ( Voltage Open Circuit ) is not too high for the Charge Controller.

YOU must do these calculations ...
a) When Hot: the minimum PV Voltage + Head Room MUST BE GREATER THAN EQ Voltage for 3 hours.
b) When Cold: the maximum PV Voltage MUST BE LESS THAN the maximum allowed input volt to charge controller.

Next, you need to plug some real values into the above formulas to determine WHAT your next step should be.
Show us your math.

If you ever enable EQ mode without being onsite you must be 100% positive that the PV Panel Voltage is high enough to complete the EQ Cycle, ASAP. Otherwise you will continue to boil the electrolyte out of your batteries - ouch.

Photowhit · September 2017

I'm sort of not surprised that a solar company wouldn't catch it. I suspect they have seen older system with similar configurations. It might be that the 2007 solar panels ran about $4 a watt and systems often ran with weaker amount of solar to Battery bank. You also have a wind generator, which would be an unknown quantity in the amount of charging, It still is!

The wind generator is an unknown quantity. It might be nice to check what you have coming in from the wind generator with a clamp meter, have you had it down for maintenance? Does it's charge controller track it's output?

I think I would equalize more often, but don't know how your battery bank is treated. I know Rolls/Surette only suggests every 6 months (or use to) Trojan contradicts it's self or use to, stating only when cells are out of balance, but produced a video below;

https://www.youtube.com/watch?v=jCl5klSF4tE

History of MPPT type charge controllers goes something like been around in one off's for a while, then Blue Sky came out with the first for solar (never a great charge controller) then I think you have then next commonly available unit. boB, who designed it, is a member here and has said that a MPPT type charge controller needs about 30% more voltage as 'head room' to work efficiently. (he may have been addressing the Midnite Classic a newer charge controller at his and brother Robin's new company) As I have stated you are below that in general. Strings of 5 might be enough. but I haven't done the math.

This was an early charge controller of this type, but it doesn't seem logical to disable the temperature sensor. This might be a good question for the Outback forum, perhaps there is a firmware update.

http://www.outbackpower.com/forum/

Something to consider if your wind charge controller is a separate unit, and for a 900 watt I would hope it is and near the battery bank. You might consider switching out both charge controllers for 2 Midnite units, I think they will be able to communicate with each other and monitor the charging going into the battery bank with their shunt based monitor (The Wiz Bang Junior)

I wish I had simple answers for you, but perhaps I at least offered some insight.

Photowhit · September 2017

BTW - I didn't go and see what Interstate's thoughts were on equalizing. I try to suggest checking with the manufacturer.

mvas · September 2017

The Charge Controller is not smart enough to determine when EQ should be performed.
EQ is not performed on a periodic cycle, not on a specific schedule, not every 6 months.
EQ is performed when the SG varies from cell-to-cell.
This can only be determined by human, with a brain.
If you are bubbling the electrolyte during normal Bulk & Absorb, then EQ will be few and far between.

Trojan recommends equalizing only when ...
low or wide ranging specific gravity (>0.030) are detected after fully charging a battery.

Photowhit · September 2017

mvas said:

The Charge Controller is not smart enough to determine when EQ should be performed.
EQ is not performed on a periodic cycle, not on a specific schedule, not every 6 months.
EQ is performed when the SG varies from cell-to-cell.
This can only be determined by human, with a brain.
If you are bubbling the electrolyte during normal Bulk & Absorb, then EQ will be few and far between.

Trojan recommends equalizing only when ...
low or wide ranging specific gravity (>0.030) are detected after fully charging a battery.

Guess you missed my video link above, so here it is again, Take a look, it is made by Trojan for their customers! They can take it down at any time;

https://youtu.be/jCl5klSF4tE

mcgivor · September 2017

Interesting video, having read the recommendations for Trojan on their website they state, equalization should only be preformed when the SG readings between 2 or more cells are more than 0.030 apart, as @mvas stated, not every 30 days as the video suggested. Wonder if this is something to do with batteries in regular cycling as opposed to those which remain in float predominantly, as cycling daily is more likely to promote sulfation, but that was not mentioned.

mvas · September 2017

No, I did not miss the video.

Doing an EQ every 30 days is for the "brain dead" / "set & forget" type people, not for maximum battery life.
Understand that Trojan must entertain a very wide audience.
There is no need to EQ the Battery Bank every 30 days unless you are chronically under-charging on a daily basis.
Some people do this - ouch!
But we have the exact opposite issue in this thread ... we have habitual over-charging.

EQ when ...
a) You have stratification - Nope you won't have that every 30 days, if you bubble the batteries during Bulk & Absorb every day.
b) If you measure SG < 1.235 - Nope you won't have that, if charge to 100% SOC every day
c) If SG varies > 0.030 points - Nope you won't have that every 30 days.

If none of the above three issues is true, then WHY is the Charge Controller doing an EQ every 30 days?
WHY?

For maximum battery life ...
a) YOU need to measure the SG
b) YOU need to decide when to start the EQ
c) YOU need to decide when to terminate the EQ
Yes, that involves using your brain.

All of the active material that is shed from the plates during an EQ is lost capacity, forever.

Tell me how shedding active material every 30 days leads to longer battery life?

Photowhit · September 2017

mvas said:

Doing an EQ every 30 days is for the "brain dead" / "set & forget" type people, not for maximum battery life.
Understand that Trojan must entertain a very wide audience.

Please note, they didn't have to post this and they can take it down any time. It would be A WHOLE LOT EASIER TO NOT EQUALIZE! So perhaps they have a reason?

I use a forklift battery some forklift battery are recommended to equalize even more often! And once a month is a minimum...

Shedding will open areas for use that were not available for use before shedding, shedding is not the only reason and higher activity will allow for additional recombining into solution.

mvas said:
All of the active material that is shed from the plates during an EQ is lost capacity, forever.

What is shed is inactive sulfating and will allow exposure to plate material that will allow for greater capacity.

We can hijack this thread or agree to disagree.

mvas · September 2017

Sulfated lead ?
What are you talking about ?
There is no sulfated lead in his battery that is already at 100% SOC and then severely over-charged with a long term Equalization Charge.
He is shedding pure lead.
He is reducing the capacity of his battery.

Photowhit · September 2017

You might search the chemistry of lead acid batteries. I don't have the time.

BB. · September 2017

Different manufacturers do have different recommendations about Equalization and how often to do it. A good start is studying the manuals for your batteries.

Such is life.

-Bill

Sakamochi · September 2017

Screen shot of the setpoint history. Interstates are last. You might find Rolls interesting. They said 20 points SG. I now go by 30.

I want to thank all those good informative replies. I appreciate that more than you know.

Discussions about when how who said whos right whos an idiot about equalizing theories etc I can care less about and it clutters and confuses up my search for help.

That said: I have not been back to my solar ranch. I am going Friday and will have more answers and questions when I return next week.

Here are some answers that I have sorted out here:

I think I am in error on the panels: my invoice says they are Kyo 130 watt not 140. I am going to confirm this Friday. If they truly are 130 w makes things a bit worse I know. I ran a spreadsheet comparing the 130/140 with all the Kyo spec data. The results seem to match what I have documented earlier: A 4 pv series panel parallel 130 w array at 47c can max out at 62 volts / 23adc (I have pix of my outback display consistently at 61vdc PV). The calculated watts are 1473 (I see 1730 max so its doing better than calculated) (I will get all current (sorry for pun) data this coming trip). The voc calculates to 79.6 vdc. The 25c numbers are 70.4vdc (I saw 71vdc on Outback) and 2080 watts (I saw 2250) and the calc voc is 87.6 vdc

SO: to answer MVAS

a) When Hot: the minimum PV Voltage + Head Room MUST BE GREATER THAN EQ Voltage for 3 hours.

NO, the system as is cannot do that above 25c.

b) When Cold: the maximum PV Voltage MUST BE LESS THAN the maximum allowed input volt to charge controller.

The Outback Max input Vdc is 150, so that is ok and has lots of room to add panel(s) in series to the 4 in play.

So I did "plug some real values and did Show us your math".

To answer Photowit:

The wind generator clamp meter is a good idea.

NO, never had it down for maintenance

Does it's charge controller track it's output?

NO. It does mimic the Outback setpoints, so it cannot over charge. If the Outback goes into absorb, the wind shunts power to the resistors.

I will check Outback forum on the EQ Temp disconnect, but I seem to remember it is a software item

The 900 watt wind gen is near the battery bank.

Concerning "consider switching out both charge controllers for 2 Midnite units", I don't think the windgen is a real factor here, it cannot over charge or equalize batteries by it self. Changing controllers is expensive and I do not see a benefit yet.

Photowit, BB and BILL:

Getting Interstate's thoughts were on equalizing is extremely difficult. I have tried online for weeks (nothing on google or their website) and now have checked with Interstate cust serv - today they sent me a pdf of a picture of the battery as their specifications. I asked again and sent them a Trojan spec sheet as an example..

Equalizing: Mcgivor et al

I have sheets and sheets of SG / temp data for the Rolls and the Interstates. That is how I knew the Rolls were dying. It is now apparent to me that I have a "MAX HEADROOM" issue with voltage and equalizing. To be clear, 10 years ago the system was set up to Auto EQ every 30 days on the Trojans, RIP. Then it was set to Auto 80 days when the Rolls were installed, RIP, all by Company "A". I was too trusting. The Interstates were left at 80 days by Company "B" but then I was there every time to watch over them equalize. If it was hot and they would not EQ I would abort and push the EQ date out. When I could not get there in time on Sept 6th that's when I finally figured it out with your help.

I think at this point to just monitor SG's as I have been, and if I am over 30 points delta SG in float I will try out my 12kw Kohler propane fired backup genset which can supply 70 volts at 40 amps if need be.

BTW That Kohler is AWESOME!! Yeah, it cost $7k installed. Never a glitch. Pumps 240vac well pump and charges batteries thru Xantrex plus takes over the house load all at the same time. Uses about 1.5 gallons per hour full on. Always comes on automatically each week at a preset time to run a 20 minute self check (does not charge batteries). Then if battery voltage drops per its program (volt level per time) it comes on automatically until it gets to float. This is a great option if you have a battery power failure. The generator starts and runs keeping your house heat on until it runs out of fuel (250 gallon tank). II used 38 gallons of fuel in two years.

Sakamochi · September 2017

This in from Outback Forum:

"I bought my MX60 in 2007. It came with the latest, greatest firmware update, v5.11. If yours has an earlier version and you want to update it you will have to ship it back to OB. FWIW, my manual also states temp compensation is disabled during EQ.

With a 48V system your MX60 can handle up to around 3000W of PV input so adding more PV is feasible. Whether it'll be adequate to equalize your battery, don't know."

mcgivor · September 2017

@Sakamochi said.
Getting Interstate's thoughts were on equalizing is extremely difficult. I have tried online for weeks (nothing on google or their website) and now have checked with Interstate cust serv - today they sent me a pdf of a picture of the battery as their specifications. I asked again and sent them a Trojan spec sheet as an example..

Interstate is a marketing company, which sells batteries manufactured by Johnson Controls, to the best of my knowledge, having engineers to answer questions is most likely not a priority, perhaps asking the actual manufacturer would be a better solution, but then again Johnson Controls is a massive conglomerate eating up smaller companies in the interest of corporate gain and the bottom line, but you never know they may be able to provide some insight, but I wouldn't hold my breath.

Sakamochi · September 2017

I have some new information from Interstate provided in a data sheet: Attached file has summary of what I have sorted out so far. It looks like 4 more 130 w panels would get me where I need to be except at 80 degrees, and nearly so even there.

Please comment on my calculations!

Also attached Intertsate spec I finally received. This is a shocker today the data sheet from Interstate: Bulk 7.35, Absorb 7.65 2-4 hours, EQ 7.8 This translates to @80f Bulk 58.8 Absorb 61.2 Float 52.8 EQ 62.4
My system could do this marginally well below @ 25C (75F). It is impossible the way it was designed and operates!!!!

I am going to get more onsite data and info tomorrow and report next week. I sure want to ask Company B what they were thinking on this system!!!

Here is the SW Windgen set points: They are OFF @57.6 vdc ON @ 52,6 vdc

Thank you

Sakamochi · October 2017

Image: https://us.v-cdn.net/6024911/uploads/editor/n0/f6862bm8l7z1.jpg

Image: https://us.v-cdn.net/6024911/uploads/editor/cs/9h8z3ouvg27a.jpg

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Image: https://us.v-cdn.net/6024911/uploads/editor/qj/64pqtz5nua7q.jpg

I have returned from the field so to speak and attached the photos to show watt is going on. It seems that on Sept 26th, when the over night temps reached 0 degrees C (32 F) and the daytime temp was about 25c (75f) that the panels and the controller were in their happy place. VOC at daybreak about 95 volts. Plenty of volts and watts. SG's were all very high and fairly level after Float (excluding Battery #13 which was born low). The excessive boiling probably helped level the SG's at the expense of plate material.

I changed the Absorb time to 3 hours. It turns out that tis where it was set from inception until about a year ago when a service tech changed it last Sept.

My panels are 130 watt as I suspected.

My conclusion for the time being is to increase 4 more panels to deal with the summer time de-rating while not over "VOC"ing in February when the daybreak temps can be negative 15 degrees F.....

Maybe adjust voltage setpoints some more based on dialogue. I have a concern that the over temp of 124 degrees and boilng may have shortened the lifespan of my 38 month old battery set...

Thank you for your help!

westbranch · October 2017

And for the depths of winter you also still have some leeway, in that you can up the ABSORB time if you are not getting the SG you want. I have a winter setting and a summer setting that I use. Lower V and shorter time in summer, winter I set both to the max recommended

Craigo · February 2018

Sakamochi - What angle are your panels facing? It sounds like they may be too vertical and may need to be laying flatter.

Boiling Mad

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