Growatt SPF5000ES is not charging the battery completely

[Paulfrench35]

Hello, my SPF5000ES does not charge the battery completely, it stops for no reason.

It indicates a full battery while the voltage is 53.6v. I set #19 and #20 to 55.1v so why isn't it charging the battery?

The BMS indicates approximately 3.351v per cell while the Remain Battery is at 99%...impossible!!!!

My settings are not correct?

 

[TomC4306]

My settings are not correct?

This.
Try charging a bit higher. Maybe 55.6.
What is your absorption time set to?

It's not ".. stopping for no reason".
There IS a reason and the answer is in your settings.

 

[Paulfrench35]

There is no absorption time, programs #19 and #20 have the same values as indicated in the manual. It's not good?

I don't have link CAN or RS485 between inverter and bms.

 

[BentleyJ]

Here are the observations based on what is posted.
1) The BMS indicates -0.4A and the arrow on the inverter display is pointing from the battery towards the inverter. This is exactly the expected voltage of an LFP battery that has been fully charged and is now sitting idle with no load or a very small discharge current. The battery must have completed a charge cycle at some point in the recent past and stopped charging. Unless the inverter enters into float mode the voltage will not be held high above the normal resting voltage.
2) The inverter shows a 4.6% load which is only 230W. So the battery is providing 53.6V x 0.4A = 21.4W and the remainder from Solar.

This behavior does not seem unusal. What specifically is the issue you are trying to solve?

EDIT: Per the inverter message regarding setting. User-Definded 2, it states that the inverter will stop charging when the battery reaches the setting. Seems like this is exactly what happened.

 

[timselectric]

19 and 20 should not be the same.
Set 19 to 55.5 , or higher.

 

[Paulfrench35]

19 and 20 should not be the same.
Set 20 to 55.5 , or higher.

Program #19 must be greater than #20 ?

 

[timselectric]

Program #19 must be greater than #20 ?

Oops
I said it backwards.
Thanks

Corrected

 

[Paulfrench35]

#19 is Bulk and #20 is Floating?

So program #19 --> 55.2v and program #20 --> 55.1V for example ?

 

[timselectric]

#19 is Bulk and #20 is Floating?

So program #19 --> 55.2v and program #20 --> 55.1V for example ?

That's too close.
Separate them by at least 0.3v.
More is better.

 

[TomC4306]

I charge at 55.6 volts. Hold that for 2 hours, then float at 54 volts.
The yellow dip is the changeover from absorption to float. Takes about 6 minutes.

 

[Crowz]

My tp6048 (which may not apply to this since its not the same) has this for option 21.

Battery stop charging voltage
when grid is available

I was set to 54v but it has an option of FUL which seems to mean fill it up

When set to full it charges till the battery is completely "full" then goes to float.

Even though it says when grid is available it will charge to full on solar when no grid available. Go figure.

 

[Paulfrench35]

I followed your advice and it works much better.

Another question, why does the inverter refuse to let me go below 50v for program #12 ?

I would like to go to 49.8v.

A special rule to follow that is linked to another program #?

 

[timselectric]

It can be set to anywhere between 44v to 51.2v .
But must be higher than setting #21.

 

[Paulfrench35]

How many volts minimum between both ?

 

[timselectric]

How many volts minimum between both ?

I don't think that there is a minimum.
So, 0.1v should be fine.
Although, I wouldn't want it that close. It would be too easy to trigger an unwanted shut down.
I would recommend at least 2v difference.

 

[Paulfrench35]

The minimum is 2v, I just tried, with 1.9v difference it doesn't work.

 

[timselectric]

The minimum is 2v, I just tried, with 1.9v difference it doesn't work.

Makes sense.
I wouldn't want it any closer.