Classic wont reach equalization volts.

[JBonfire]

My 150 classic won't go above 31.5v (stays there even when batteries are full) when choose equalization (target 32.4v).

This is the second time it has happened.  I started the equalization at 10am.

[Vic]

Hi JBonfire,   Welcome to the Forum.

Is the Charge Controller (CC) in EQ-MPPT?

Have you set the CC to compensate the EQ voltage?  If so,  in the Temp(eratures) Menu,  what is the battery  voltage?  If the batteries are warm,   and the EQ voltage is compensated,   then you have reached the EQ voltage.

If the CC is in EQ-MPPT,   this means that there is not enough power (probably from PV),  to reach the EQ voltage setpoint.   If there are significant loads on the inverter,  you might want to reduce these to see if that helps.

Assume that you are off-grid.  And assume that you are not using the Local App to monitor the Classic.

Later, Vic

[JBonfire]

Is the Charge Controller (CC) in EQ-MPPT?
Yes

Have you set the CC to compensate the EQ voltage?
No, unless I did that accidentally (still learning a lot). How do I check?

Batteries 102.6F
Pv array is producing 1737W+1210W=2947W between the two classics.
I had no loads ( I had disconnected the inverter)

I am off-grid and I have the Local App to monitor the Classic.

Thanks for helping

[Vic]

JBonfire,   thanks for the added info.

SO,  EQ-MPPT means that there is simply not enough PV power to reach the EQ setpoint.

Ideally,   one would do the EQ after the Absorb stage is completed (or,  at least almost all of the Absorb).

OK on no EQ temp compensation.

As the EQ progresses,   the amount of current needed will usually decrease,   but,  the batteries will become warmer,  as the EQ process proceeds (even if the ultimate EQ V has not been reached).

Is there a Sulfur aroma around the batteries.   This is a sign that,  even at the 51.5 volts the initial stages of the EQ are getting done,   if you have enough time for the PVs to get the job done.

You may need to take a run at the EQ,  over several days.   If you have a generator,  and your
Inverter has a charger,  you may be able to use it to help,  if the inverter/charger can reach the dewired EQ voltage.

I would call batts at 102 F,  HOT.

It does sound as if your batteries DO need an EQ.

What is the brand,  model number,   and Ah Capacity of your battery bank?

Later,  Vic

[boB]

Just to make sure, go into the menu (LIMITS I think) and check that the MAX temperature compensated voltage is not set below that voltage you are wanting this to get up to.

That value SHOULD bump up from your default voltage settings but just in case I am wrong about that...

[Zardiw]

Have the same issue.

During the day, the array puts out enough power to max out the controller at noon...... 90 or so amps. (14 Panels)

These are 4 Trojan 6V L16's that require 32.4 V for Equilization. (I disconnected the 12 2V Battery Bank)

Right now have it set to equalize and has been there all day.

Batteries were pretty much fully charged when I started.

Individual Batt V: 7.30, 7.22, 7.28, 7.34

Nothing is hooked to inverter:

Battery Voltage 29.4
Amps: 9.5
Watts 275
Input Volts 66
Temp Compensation is not set on
Battery Temp 32.2


z

[Vic]

Hi z.,

OK,  so at the time  that you noted the battery voltage  of 29,4,  the CC was in EQ-MPPT?   Seems that this was probably fairly late in the day,  and the sun was fading,  the PVs were partially shaded,  ete ??

Do you know the maximum voltage  and current that  was  reached,  during this EQ.  Did the CC ever reach the target EQ voltage?

AND,  as boB  noted,  above,  please check  the  Charge>Temp Comp>Limits menu,  to make certain that the High voltage  Limit  is NOT limiting the voltage.

The batteries are not particularly warm   ...   so it seems that perhaps not  too much EQing was happening for an "all day" EQ attempt.

It does appear that this battery does  need a bit of an EQ,  just based on the variation in battery voltages.

Later,    Vic

[Zardiw]

No.

I started EQ-MPPT early in the day (Batteries were mostly charged from the previous day, and inverter was disconnected at EOD the day before, in anticipation of trying to do the EQ the next day).

Readings were at High Noon........Hence the problem of not reaching 32.4 volts.......instead only putting out 277 Watts.......when the array is capable of putting out 2,000 Watts .....which it consistently puts out daily.

It never reached 32.4 .......it stopped when it reached 29.4 something volts, and decreased wattage significantly.... that's the issue we're talking about......

Limits:
Output Amps: 94 ........Input Amps: 99
Minimum Volts: 26.4 ....... Maximum Volts: 70

I don't know what those are supposed to do.....or why they are even there......

Compensate Equalize Voltage is NOT CHECKED.

Values are -5 mv/C/Cell ........... Compensation 28.5V
Temperature Window (C) : 25

Controller is in Legacy P&O ......Not sure what that is either, as opposed to Solar.

Don't know why there is an On/Off selection either......is that so the controller can be turned on/off?

Using the MidNite Solar Status Panel.

I'm 100% sure that it's something I'm doing.......since all software/hardware built by companies in the 21st century is perfect and without any flaws......based on responses to any problems I've had with such (clear cache, remove cookies, re-install windows, etc)



z

[Vic]

No.

I started EQ-MPPT early in the day (Batteries were mostly charged from the previous day, and inverter was disconnected at EOD the day before, in anticipation of trying to do the EQ the next day).

Readings were at High Noon........Hence the problem of not reaching 32.4 volts.......instead only putting out 277 Watts.......when the array is capable of putting out 2,000 Watts .....which it consistently puts out daily.

It never reached 32.4 .......it stopped when it reached 29.4 something volts, and decreased wattage significantly.... that's the issue we're talking about......

Limits:
Output Amps: 94 ........Input Amps: 99
Minimum Volts: 26.4 ....... Maximum Volts: 70

I don't know what those are supposed to do.....or why they are even there......

Compensate Equalize Voltage is NOT CHECKED.

Values are -5 mv/C/Cell ........... Compensation 28.5V
Temperature Window (C) : 25

Controller is in Legacy P&O ......Not sure what that is either, as opposed to Solar.

Don't know why there is an On/Off selection either......is that so the controller can be turned on/off?

Using the MidNite Solar Status Panel.

I'm 100% sure that it's something I'm doing.......since all software/hardware built by companies in the 21st century is perfect and without any flaws......based on responses to any problems I've had with such (clear cache, remove cookies, re-install windows, etc)



z

'Morning  z,

Off to do chores,  this AM.

But,  one question:   What is the input voltage to the Classic,   when you are seeing EQ-MPPT,  and the 270-ish watts of power?

There are very good reasons for all of the functions,  that are built into the Ckassic CC.

Later,   thanks,   Vic

[Vic]

Hi z..,

OK,  in re-reading your initial post,  you note that the input voltage is 66 V,   does it remain in this range throughout the EQ process?

You can look at Data to see the battery voltage,   power,  etc,   to help you understand what is going on during EQs.

If the Classic is in EQ-MPPT when you are seeing this relatively low power output,   then the Classic is saying that this is the maximum amount of power available from the charge sources (probably just PVs).

Please check the Firmware version of the Classic,   what is that?
What is the Voc when you see this low power production in EQ-MPPT?
Did you try using Solar Mode?
When you saw the low production in EQ,  how high in the sky was the sun,  and  were the PVs oriented at right angles to the sun,   and was there ANY SHADING of the PVs,  at all?
What is the Absorb voltage setting?
These Trojan batteries are Flooded,   have you taken the SG readings,  recently,  with your accurate Hydrometer (or Refractometer)?  What are those readings?

The Classic Manual explains most of the functions that are built into the Classic firmware.
The voltage Limits,  do just that that:  Keep the charging voltages within the range of those settings.   Some batteries need this.

Thanks for the answers.   Vic

[Zardiw]

That's a lot of hoops to jump through Vic.............not even gonna try......lol.

Bottom Line: There was AMPLE power from the panels. AMPLE.......WAY MORE than enough to go to 32.4 volts.

But the controller decided to stop at 29 something.......dialed the watts WAY down.....I've got 14 panels OK?

I've given you all the data you should need in MULTIPLE posts.

Seems like you're just looking for something...ANYTHING that would justify the controller screwing up.......lol

ReRead what I wrote, and try to find out why it won't go to 32.4 volts...........Maybe there's a bug??

Has anybody ELSE gotten this thing to go to 32.4 volts?

What about Batteries being a few years old?......Would that do it?

There should be a data item that lists what voltage the Controller is putting out.........instead of just the system voltage.

z

[Vic]

Hi z,  Thank you so much,  for accommodating my many questions.

Here is the thing: If the Classic in showing EQ-MPPT,  then,  there is insufficient PV Power to raise the voltage any farther.

You should check your firmware version,  and Update if the Classic FW is not at 2126,   or higher.   Updating to the latest Firmware is always recommended.

Wish you the best. Some modicum of cooperation is often helpful.  After all,   most of us here are just volunteering our TIME.  If you do not have the TIME to try to help us help you,    then,  you might be on your own.

Details DO matter   ...

My Classics  readily reach 65.5 Volts in EQ.,  when cold.   ALL the Flooded banks here are in their 15th year of service.    If your battery has not been EQed  for months,   then it can take quite a bit of time to reach the EQ setpoint.

Will add:  If the present Trojan batteries have been sidelined for some extended period of time,   neither being charged nor cycled,   Hard Sulfation could have developed on the plates.   This can result in the battery not Accepting much charge current,  and not being able to deliver mush current on discharge.
BUT,  this would usually result in the CC reaching the Absorb or EQ setpoints rather quickly,   and then not be in  Bulk-MPPT,   or EQ-MPPT.

All the Best.   Out of time,  here.   Vic

[boB]

There is one question that I don't think has been answered that is very important...

What voltage are your panels at when the battery voltage is just below the EQ setting of 32.4 volts ?

OR, what is the Voc (open circuit voltage)  of the array coming into the Classic PV input ?

If the PV input voltage is say, 50 volts then yes, something is definitely wrong.

But if the PV input voltage at that time is something just above that 32.4 EQ volts, then your PV array needs to be wired for a higher voltage.

The Classic can only buck the input PV voltage down.  It cannot boost that  PV input voltage up higher.

There may be ample "power" but if the "voltage" on the input is not several volts (or at least  few volts) higher, then it cannot bring the battery volts up to that voltage.  The power available would be below 32.4 volts

One setting that may help this, IF it is turned OFF now is called Low-Max in the TWEAKS menus.  Make sure that is turned ON.
This will make sure that the PV input voltage, if low-ish, will go as low and as close to the battery voltage as possible.  It should be already turned ON but make sure.

If the PV input voltage is high enough, say, 40 or 50 volts, then Low-Max should not be necessary.

You asked about the ON/OFF position in the MODE menu.  Yes, that is there to be able turn the function OFF while doing other things but being able to still look a the Classic meters.  Voc is the important value as far as my questions here and voltage at max power point.
Has to be higher than the wanted battery voltage by some minimum amount in order to bring that battery voltage up to your wanted 32.4 volts.

If it is going to take an appreciable amount of power to EQ your batteries, let's say, 1000 watts, then you will need the PV to have a maximum power point voltage at least as high as your EQ voltage.   Typically max power point is around 80% of open circuit voltage (off voltage) Voc.
In your case, your Voc would want to be at least ever so slightly higher than 32.4V X 1.25 = 40.5 volts Voc.

If your Voc is lower than around 41 to 42 volts, you may need to re-wire the PV array for a series voltage that is maybe twice as high to divide up the array properly to get there.

Thanks,
boB

[Zardiw]

I'm sorry for being a bit short with all this .......it's just frustrating to me.

During High Noon, my PV array puts out Over 2,000 watts at a voltage higher than 60V.

When I was trying to Equalize, it was all day long.....I live in PS, California, and the sun is Hot and Bright here.

There is NO WAY my array could have been putting out insufficient power......no way.

Yet, the controller had it dialed down to 277 watts......

I'll try to provide screenshots........or maybe a Video to show all this today.......

z

[Zardiw]

Once again, sorry for being a pendecho earlier.....

I have 14 panels. 7 pairs of 2 each in series. (VoC on those is about 37v)

Also 2 Battery Banks. 1) 4 6v L16 Trojans and 2) 12 2v L16 Trojans.

At the time I tried Equilization, I'd disconnected Bank 2 (12 - 2V) and was trying to Equalize the 4 6V Trojans.

Here's a video of my settings. (Maybe my settings are wrong......I have no idea)

https://www.youtube.com/watch?v=kYc1YhDQEjo

Also have no idea how to upgrade Firmware (2193 currently).....maybe I need to read the manual.......lol

z