Victron MPPT 150/35 stuck in float

[ClaeTA]

Hey folks, I'm exhausted looking for the answer to my issue and overwhelmed by the varying information thats out there.
I have a trailer with 3 X 220w panels in series tied to my Victron MPPT 150/35 charge controller into to two LiTime 12v 100ah batts in Parallel moniotred by a Victron shunt.
The "SmartSolar" charger can be configured 1 of three ways to work with Lipo batteries, either by using the battery type drop down in the Victron app, by using expert mode and selecting all the settings yourself or by selector switch on the controller itself.
I have tried all three and I cannot get this charger out of float regardless of the battery capacity level and the external conditions.
Today the battery level is approximatley 60% capacity, full sun from 1230-3pm and the system only after a hard reset will enter into Bulk for a moment then go right into float?
I've seen dozens of questions regarding this issue but yet to come across an direct answer.
I'd greatly appreciate any direction here, thank you

 

[sunshine_eggo]

Hey folks, I'm exhausted looking for the answer to my issue and overwhelmed by the varying information thats out there.
I have a trailer with 3 X 220w panels in series tied to my Victron MPPT 150/35 charge controller into to two LiTime 12v 100ah batts in Parallel moniotred by a Victron shunt.
The "SmartSolar" charger can be configured 1 of three ways to work with Lipo batteries, either by using the battery type drop down in the Victron app, by using expert mode and selecting all the settings yourself or by selector switch on the controller itself.
I have tried all three and I cannot get this charger out of float regardless of the battery capacity level and the external conditions.
Today the battery level is approximatley 60% capacity, full sun from 1230-3pm and the system only after a hard reset will enter into Bulk for a moment then go right into float?
I've seen dozens of questions regarding this issue but yet to come across an direct answer.
I'd greatly appreciate any direction here, thank you

Note that Expert settings are not specific to battery type or voltages as you stated. It is for :

Re-bulk offset
Absorption duration type and tail current.
Equalization current percentage
Equalization stop mode.
Maximum equalization time.

Even if unselected, the "Expert" values coded are still in effect.

There are 3 ways to specify lithium battery:
1) Select preset
2) Rotary switch
3) User defined

One of three things is happening:
1) disconnect between MPPT and battery.
2) BMS stopping charge.
3) MPPT improperly configured.
4) MPPT malfunctioning.

Have you tried a different charger to see if the batteries will accept a charge?
Have you tried charging a different battery with the MPPT?

 

[ClaeTA]

Note that Expert settings are not specific to battery type or voltages as you stated. It is for :

Re-bulk offset
Absorption duration type and tail current.
Equalization current percentage
Equalization stop mode.
Maximum equalization time.

Even if unselected, the "Expert" values coded are still in effect.

There are 3 ways to specify lithium battery:
1) Select preset
2) Rotary switch
3) User defined

One of three things is happening:
1) disconnect between MPPT and battery.
2) BMS stopping charge.
3) MPPT improperly configured.
4) MPPT malfunctioning.

Have you tried a different charger to see if the batteries will accept a charge?
Have you tried charging a different battery with the MPPT?

Thank you for providing some direction here, I did confirm that the MPPT is connected to the battery then ended up replacing the 30a fuse with a 40a and noticed the voltage to the batts increased.
While using the app I could see the voltage drop to zero when the fuse was opened then climb when closed.
Thru the app I changed it to Select preset and the system immediately went into absorption mode.
Here are some screen shots hopefully this tells a better story.
Also the error is a high voltage alarm on the battery which I havent seen before?

 

[sunshine_eggo]

The very high battery voltages logged by the MPPT are indicative of the battery BMS cutting the unit off. The unit can't react quickly enough when the battery charge load is removed, and the voltage spikes.

This is most commonly caused by one or more cells in the battery hitting max voltage triggering BMS cut-off. This is relatively common even on new batteries.

Set MPPT to Lithium, lower absorption to 13.8V and set float to 13.7V.

Set fixed absorption time
Set 4 hour absorption time
Disable tail current.

Observe behavior.

 

[ClaeTA]

The very high battery voltages logged by the MPPT are indicative of the battery BMS cutting the unit off. The unit can't react quickly enough when the battery charge load is removed, and the voltage spikes.

This is most commonly caused by one or more cells in the battery hitting max voltage triggering BMS cut-off. This is relatively common even on new batteries.

Set MPPT to Lithium, lower absorption to 13.8V and set float to 13.7V.

Set fixed absorption time
Set 4 hour absorption time
Disable tail current.

Observe behavior.

The absorption values cannot be changed under the facotry lithium setting I used the user defined.
The system went into bulk charge immediately.
Thank you

 

[sunshine_eggo]

The absorption values cannot be changed under the facotry lithium setting I used the user defined.
The system went into bulk charge immediately.
Thank you

You should be able to select Lithium to establish all the desired defaults. Then once you change absorption it should switch over to User defined.

 

[ClaeTA]

The very high battery voltages logged by the MPPT are indicative of the battery BMS cutting the unit off. The unit can't react quickly enough when the battery charge load is removed, and the voltage spikes.

This is most commonly caused by one or more cells in the battery hitting max voltage triggering BMS cut-off. This is relatively common even on new batteries.

Set MPPT to Lithium, lower absorption to 13.8V and set float to 13.7V.

Set fixed absorption time
Set 4 hour absorption time
Disable tail current.

Observe behavior.

So I’ve been running with the new settings for ~24hrs and here is today performance. Although the system appears to be operating “better” I’m not yielding much as a result.

 

[sunshine_eggo]

So I’ve been running with the new settings for ~24hrs and here is today performance. Although the system appears to be operating “better” I’m not yielding much as a result.

What do you mean by this? Based on the Wh numbers, it's higher than 3 of the four prior days.

Comparing it to the prior day, it was the same amount of bulk and almost the same amount of absorption.

Are you saying the battery does not have enough capacity for your needs?

Where did the shunt finish?

 

[ClaeTA]

What do you mean by this? Based on the Wh numbers, it's higher than 3 of the four prior days.

Comparing it to the prior day, it was the same amount of bulk and almost the same amount of absorption.

Are you saying the battery does not have enough capacity for your needs?

Where did the shunt finish?

I mispoke for sure I see my error in that the yield was 190w today even though over cast was in fact greater than the previous days before the settings were changed. I've been watching the smart meter batt % value which continues to drop. Today now at 55%. My trailer is under absolute minimum load so I expected to see this value increase today.
I'll open the DC isolation switch and see if the reduction in parasitic load helps tomorrow as the weather is forcasted to be the same.

I'm still learning here, how/where do I see where the shunt finished?

 

[sunshine_eggo]

I mispoke for sure I see my error in that the yield was 190w today even though over cast was in fact greater than the previous days before the settings were changed. I've been watching the smart meter batt % value which continues to drop. Today now at 55%. My trailer is under absolute minimum load so I expected to see this value increase today.
I'll open the DC isolation switch and see if the reduction in parasitic load helps tomorrow as the weather is forcasted to be the same.

I'm still learning here, how/where do I see where the shunt finished?

Go into the Trends tab of the shunt and select battery voltage and current. Once selected, it should track and log those values (and all others I think) for 45 days.

You should be able to track any parameter based on the log.

Please include the smartshunt settings.

The hope here is that you are able to hold the battery at elevated voltage for sufficient time to allow the BMS to balance the cells. This may take several days.

 

[ClaeTA]

Go into the Trends tab of the shunt and select battery voltage and current. Once selected, it should track and log those values (and all others I think) for 45 days.

You should be able to track any parameter based on the log.

Please include the smartshunt settings.

The hope here is that you are able to hold the battery at elevated voltage for sufficient time to allow the BMS to balance the cells. This may take several days.

Thank you, I’ve set the trend log as recommended, the trailer will be going to storage tomorrow but the solar will remain active and I’ll check on it daily to see how it’s responding.

 

[ClaeTA]

Note that Expert settings are not specific to battery type or voltages as you stated. It is for :

Re-bulk offset
Absorption duration type and tail current.
Equalization current percentage
Equalization stop mode.
Maximum equalization time.

Even if unselected, the "Expert" values coded are still in effect.

There are 3 ways to specify lithium battery:
1) Select preset
2) Rotary switch
3) User defined

One of three things is happening:
1) disconnect between MPPT and battery.
2) BMS stopping charge.
3) MPPT improperly configured.
4) MPPT malfunctioning.

Have you tried a different charger to see if the batteries will accept a charge?
Have you tried charging a different battery with the MPPT?

Thank you for providing some direction here, I did confirm that the MPPT is connected to the battery then ended up replacing the 30a fuse with a 40a and noticed the voltage to the batts increased.
While using the app I could see the voltage drop to zero when the fuse was opened then climb when closed.
Thru the app I changed it to Select preset and the system immediately went into absorbtion mode

So here is where I’m not understanding why the batteries are in float.
The charge % of the batts is 54%, and the charge state is float? With the level at which the batteries are at and the potential solar generation available (see pic) what is keeping my system from being in bulk?

 

[sunshine_eggo]

We have established that you are having an issue with the battery triggering charge protection and causing the MPPT voltage to spike and terminate charging.

Your batteries are imbalanced. This is problem #1 and must be addressed first.

At this time the SoC value is irrelevant except as a relative reference.

Please expand the Trends tab to a timeframe that includes all charging for today showing battery voltage and battery current and post that image.

 

[ClaeTA]

We have established that you are having an issue with the battery triggering charge protection and causing the MPPT voltage to spike and terminate charging.

Your batteries are imbalanced. This is problem #1 and must be addressed first.

At this time the SoC value is irrelevant except as a relative reference.

Please expand the Trends tab to a timeframe that includes all charging for today showing battery voltage and battery current and post that image.

How’s this?

 

[sunshine_eggo]

Nice. NO voltage spikes, and it's delivering at least a little current the whole time.

For tomorrow, set absorption to 13.9 and float to 13.8V. If you observe a voltage spike > absorption, revert back to the prior settings.

Your battery is likely at a high state of charge, but your shunt doesn't know that until it hits the sync criteria, and it might with the new settings. That's not an indication that the problem is fixed. It's a result of changing settings.

You're observing a small drop in SoC because the charging isn't 100% efficient per the shunt settings... 98%.

 

[ClaeTA]

Got it! Returing the trailer back to storage now, I'll check on it tomorrow around noon and let you know how its going.

 

[ClaeTA]

Got it! Returing the trailer back to storage now, I'll check on it tomorrow around noon and let you know how its going.

Here is todays trend.

 

[sunshine_eggo]

I see no spikes. Did the shunt sync to 100%?

For tomorrow, try 14.2V absorption and 13.8V float.

 

[ClaeTA]

I see no spikes. Did the shunt sync to 100%?

For tomorrow, try 14.2V absorption and 13.8V float.

It did! Here’s the trend.

 

[sunshine_eggo]

Since it's set for 13.8 and the MPPT hit 13.9 for 4 hours at low current, it synched.

The goal is to eliminate the BMS cutting charge due to imbalance. Looks like you're pretty close. Once you can get to 14.4V and hold for 1 hour w/o a spike, you're there.

Once there:

MPPT:
14.4V Absorb for 30 minutes
13.5V float

Shunt:
14.2V charged voltage
6% tail current