Does the BMS have to be connected to the inverter?

[Gulam Solar]

I'm preparing to connect a 20kwh LiFePo4 pack (when it arrives) to a Solis hybrid inverter.

I've been advised by Solis support that I have 2 options on connecting them (unofficially that is. Officially they don't support DIY batteries).

1 - connect the batteries using the PylonTech option in the Solis menu. Use a Can cable to connect the BMS to the Solis and it should (but not guaranteed) communicate OK.

2 - connect them using the default Lead Acid setting on the inverter, and don't bother connecting the Can cable. The battery parameters can be entered on the Solis and it will then be able to estimate the SOC.

However a friend of mine who built his own battery has told me that there is no point in having a BMS, if it isn't communicating with the inverter because the BMS's only function is telling the inverter to stop when it's supposed to.

So who is right?

Dears

Your friend is 100% wrong in my opinion, because the of The function of the bms.

Solis support are correct, but the problem here is that the bms of the batteries and the solis have different communications protocols. So this won’t work either.

If possible you are better off changing your inverter and design your system around the batteries.
The are a couple of makes out there that are suitable. Phocos all grid or the growatt to name a couple, I’m sure there are more out there.

 

[Coda]

Screens of my Solis, here:

5 new items by APO 33

photos.app.goo.gl

And yes, step 1:
Battery:user definie
Step 2
Battery plomb acide

Normally is same on my Solis and BMS Seplos

Thanks for the photo's, really useful.
Another question for you: when you installed the AC10R meter that comes with the Solis inverter, did you install the Current Transformer pointing to Grid or away from Grid?
Mine is pointed away from grid (reverse of what instructions say). The 2 red lights on the meter light up when there is no solar and I'm importing from grid, and they are normal (off) when I am exporting from solar to grid.

I am not sure that this is correct, but I think there is possibly a bug in the Solis firmware - if I am reading the main status page correctly, it shows electric flow arrows between House and Grid the wrong way around...

 

[Sanwizard]

So first you set "user-defined" then you set "lead-acid"?
Also, what voltages have you set for user-defined profile? I still haven't set mine properly.

I will look at the Seplos Battery Monitor software. It may be that there's a different profile pair that can be used instead of Pylon, like BYD.

Also, I'm going to write to Seplos and ask why their Pylontech profile causes fault on Solis inverter.

Merci.

Please provide your cable pinouts also.

 

[arnaudpo33]

Merci pour les photos, vraiment utiles.
Une autre question pour vous : lorsque vous avez installé le compteur AC10R fourni avec l'onduleur Solis, avez-vous installé le transformateur de courant pointant vers le réseau ou hors du réseau ?
Le mien est pointé loin de la grille (inverse de ce que disent les instructions). Les 2 voyants rouges sur le compteur s'allument lorsqu'il n'y a pas d'énergie solaire et que j'importe depuis le réseau, et ils sont normaux (éteints) lorsque j'exporte de l'énergie solaire vers le réseau.

Je ne suis pas sûr que ce soit correct, mais je pense qu'il y a peut-être un bogue dans le micrologiciel Solis - si je lis correctement la page d'état principale, elle affiche les flèches de flux électrique entre House et Grid dans le mauvais sens...

 

[arnaudpo33]

Here are some pictures for the setting and wiring of the meter ACREL ACR10R:

7 new items by APO 33

photos.app.goo.gl

If the Solis is counting backwards, you have either positioned the clamp in the wrong direction.

Or, what happened to me is that the original meter delivered with the Solis was not compatible!

Since I have this one ACR10R, everything works perfectly on this side. (which is far from being the case with the Solis!

 

[Coda]

Here are some pictures for the setting and wiring of the meter ACREL ACR10R:

7 new items by APO 33

photos.app.goo.gl

If the Solis is counting backwards, you have either positioned the clamp in the wrong direction.

Or, what happened to me is that the original meter delivered with the Solis was not compatible!

Since I have this one ACR10R, everything works perfectly on this side. (which is far from being the case with the Solis!

Thanks.
Solis is not running backwards, but the AC10R meter current transformer clamp is fitted opposite how the arrow shows (grid arrow points away from grid, not towards it). This means that when pulling power from the grid the meter shows apart from the normal green and red LEDs, 2 more red LEDs (R_P = reverse polarity - the other I do not know what it means). When exporting to the grid (excess solar incoming) the meter looks normal (one green LED and one red LED that flashes to show some amount of power has passed).
This must be correct, because if I turn the clamp around and reverse the logic, the Solis immediately starts pulling 5.5KWh from the grid to charge the battery.

I would take a photo but my iphone camera is damaged (never fix a modern phone to a high-performance motorcycle ?‍ )

 

[arnaudpo33]

Thanks.
Solis is not running backwards, but the AC10R meter current transformer clamp is fitted opposite how the arrow shows (grid arrow points away from grid, not towards it). This means that when pulling power from the grid the meter shows apart from the normal green and red LEDs, 2 more red LEDs (R_P = reverse polarity - the other I do not know what it means). When exporting to the grid (excess solar incoming) the meter looks normal (one green LED and one red LED that flashes to show some amount of power has passed).
This must be correct, because if I turn the clamp around and reverse the logic, the Solis immediately starts pulling 5.5KWh from the grid to charge the battery.

I would take a photo but my iphone camera is damaged (never fix a modern phone to a high-performance motorcycle ?‍ )

Hi,
any news about your installation?
Regards.

 

[Coda]

Hi,
any news about your installation?
Regards.

<je suis desole - long rant!>

Hi, Yeah I think it's mostly working according to expectations. However, I had to re-flash the latest DSP firmware for it to start behaving itself, and several times I adjusted battery storage settings, but I am not sure which (if any) of those changes fixed it.

The latest problem I have, I noticed when we had a couple of days of bright sun last week. My 14.5KWh battery connected to the Seplos BMS went to 100% fully charged (Yippee!) BUT the BMS decided the battery pack was above maximum voltage (limit was set to 54V) so the BMS cut off the battery. Well, that is a good thing, and a good test of battery protection. But what did the Solis inverter do when it detected over-voltage signal from the BMS?

Instead of just diverting the solar to power my loads as normal, IT COMPLETELY SHUT DOWN THE SOLAR GENERATION!

I only noticed when I used the microwave to reheat some coffee... I have a smart meter and the display which sits near the microwave showed me I am eating 1.2KW from grid, when I could see the sun burning outside! IMO this is a massive bug in the inverter.

I need to adjust the protection voltages on the BMS, and I need to set a % SOC maximum. That may prevent the whole inverter from shutting down when the pack is fully charged...

 

[GXMnow]

This is something I have tried to explain to a few different people. The BMS should never be the device that ends a charge or discharge cycle. It is just a safety device incase something goes wrong. When the BMS shut off, the inverter saw it as a major fault. That is completely normal.

My charger stops charging about 2 volts below the full 58.8 volt charge point where my BMS would shut off. And when it is inverting, I have it shut off at about 50% state of charge, 51.5 volts instead of the 44.8 where the BMS would shut off. When I had a balance lead fail, and the BMS did shut down, it also locked up my Schneider inverter until it saw proper battery voltage again.

 

[ronnie263]

Time will tell soon enough, my batteries are due in about 2 weeks so I'm back to harass @the_colorist with more questions

This is my current battery connection.

View attachment 47756View attachment 47757
View attachment 47758

Do I need anything more here or can I literally just disconnect the PylonTech and connect up the LiFePo4 set? The emergency switch should function the same?

Hello.

Did you have any challenges with the Pylontech perfomance wise?

 

[Eddperk]

I’m UK based with a Solis 5G hybrid and looking to add a self-assembled LiFePo4 pack soon (planning 16S 200ah) and looking back through this thread I can see the following options:

ZEVA BMS - works but discontinuing support
Seplos BMS - works but requires the Solis ‘user define’ option which may be removed in future firmware.

Am I correct? Anyone know of other viable options at the moment?

 

[shavermcspud]

I’m UK based with a Solis 5G hybrid and looking to add a self-assembled LiFePo4 pack soon (planning 16S 200ah) and looking back through this thread I can see the following options:

ZEVA BMS - works but discontinuing support
Seplos BMS - works but requires the Solis ‘user define’ option which may be removed in future firmware.

Am I correct? Anyone know of other viable options at the moment?

I have the Solis 6kW Hybird 5G and DIY LFP with the seplos 200amp BMS, Set the inverter to AoBo battery type and all it good

 

[Eddperk]

I have the Solis 6kW Hybird 5G and DIY LFP with the seplos 200amp BMS, Set the inverter to AoBo battery type and all it good

Thanks, that’s good to hear. It was the user defined battery profile which Solis states in their manual is not for end user use which was bothering me.

 

[eniacs]

<je suis desole - long rant!>

Hi, Yeah I think it's mostly working according to expectations. However, I had to re-flash the latest DSP firmware for it to start behaving itself, and several times I adjusted battery storage settings, but I am not sure which (if any) of those changes fixed it.

The latest problem I have, I noticed when we had a couple of days of bright sun last week. My 14.5KWh battery connected to the Seplos BMS went to 100% fully charged (Yippee!) BUT the BMS decided the battery pack was above maximum voltage (limit was set to 54V) so the BMS cut off the battery. Well, that is a good thing, and a good test of battery protection. But what did the Solis inverter do when it detected over-voltage signal from the BMS?

Instead of just diverting the solar to power my loads as normal, IT COMPLETELY SHUT DOWN THE SOLAR GENERATION!

I only noticed when I used the microwave to reheat some coffee... I have a smart meter and the display which sits near the microwave showed me I am eating 1.2KW from grid, when I could see the sun burning outside! IMO this is a massive bug in the inverter.

I need to adjust the protection voltages on the BMS, and I need to set a % SOC maximum. That may prevent the whole inverter from shutting down when the pack is fully charged...

Coda i have exactly this problem. Using solis/seplos/lfp. Have you managed to solve it? Ive tried reducing a few of the charge voltages on the inverter to below the 57.6v of the bms pack protection. However it still appears to charge when is shouldnt.

 

[shavermcspud]

Coda i have exactly this problem. Using solis/seplos/lfp. Have you managed to solve it? Ive tried reducing a few of the charge voltages on the inverter to below the 57.6v of the bms pack protection. However it still appears to charge when is shouldnt.

See my post above, change battery type on inverter to AoBo, it sorts all the issues out that using the default mode gives you.

 

[Coda]

Coda i have exactly this problem. Using solis/seplos/lfp. Have you managed to solve it? Ive tried reducing a few of the charge voltages on the inverter to below the 57.6v of the bms pack protection. However it still appears to charge when is shouldnt.

I basically just started ignoring it. After I changed some of the voltages so it would charge higher before it cut out.
I need to revisit it but too many other things are grabbing my attention at the moment.

 

[eniacs]

See my post above, change battery type on inverter to AoBo, it sorts all the issues out that using the default mode gives you.

Thanks for getting back to me. I've tried changing it, but the inverter shows Batname fail alarm? Do i need a firmware upgrade or do you just live with that alarm?

 

[shavermcspud]

Thanks for getting back to me. I've tried changing it, but the inverter shows Batname fail alarm? Do i need a firmware upgrade or do you just live with that alarm?

Have you changed the BMS to Sofar can comms? if not then you will get this error

 

[eniacs]

Changed it over and no error thanks for the help. Will see how tomorrows charge goes!

 

[eniacs]

No luck, 2 Alarms today. Same as befor

I just left the settings as standard, did you change anything?