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Seplos Mason Issues :(

Rickster1978

New Member
Joined
Nov 5, 2023
Messages
66
Location
Hereford
Hi all

Back for a little bit of advice as something appears to have gone wrong with my Seplos Mason battery.

All was fine before I went on holiday. I’ve got back and realised that the battery is charging very slowly and only able to add about 5% over the Octopus off peak charge time (11:30pm - 5:30am).

Looks like I’ve found the moment where something went wrong:

IMG_6011.jpeg
At about 2am there seems to be an increase in the BMS temperature and from there on the charge slows down.

Any ideas what this could be? I’ve tried pressing the reset button on the Seplos Mason and then activated the charge again but still getting the slow charge times.

What would be the best next steps? I’m using a Sunsynk Inverter but assuming this is a battery problem.

I’ve got the BMS IPhone app but the previous password of 11111 and username admin don’t seem to work anymore. That’s the only way I’ve ever looked at any of the BMS data previously.

Im at a complete loss as to what’s gone wrong. Any advice would be greatly appreciated. I’ve asked a couple of the FB groups but it seems to have confused everyone.
 
Whilst there is a blip on BMS temperature, it's not really that hot IMHO. Looks like it goes up from 25C to 35C max, but then drops after the charge rate reduces. What is more odd to me is the sudden (reported) reduction of charge current, but that returns back to 100A straight away.

The flattening of the charge curve suggests to me that the battery is nearing its maximum SOC - possibly on some cells and not all - and for that reason the BMS is demanding a lower charge rate from your inverter. That could be indicative of cells going out of balance.

That's just a wild guess though as I don't have Sunsynk or Seplos system, but I'll tag @houseofancients who is the Sunsynk + Seplos guru around here, hope he may be able to make some suggestions.

Is the battery still capable of discharging?
... looks like it has been discharging from 75% to 62% between 05:30 and midday.
 
Yes, if the battery can still discharge and only charging is blocked, it means the BMS has disabled charging because it detected a problem with one of the cells. The blip in temperature was the BMS dissipating power as it cut the charging current.

If the battery can't charge or discharge, I'd tend to think the BMS has failed and the temperature blip was it burning out. This would explain the lack of Bluetooth comms.

Another possibility might be a faulty temperature sensor reporting a bogus high temp that causes the battery to disable itself.

Does the battery have a display? What does the display show?
 
Thanks for the replies, houseofancients helped me a lot previously so hoping they are around to assist :)

The battery does still discharge and also charges but at a very slow rate.

The display on the front of the Seplos doesn’t seem to show any faults. I can’t currently find the cable to connect it to the laptop. I’ve got a horrible feeling I got rid of it when I started using the Bluetooth app instead. I’m not sure if it can view individual cell information on the Seplos display, I have a feeling I need to connect it to the app / laptop to view that.
 
realised that the battery is charging very slowly and only able to add about 5% over the Octopus off peak charge time (11:30pm - 5:30am)
Just looked at the graph again. It has actually charged up more than that... from about 54% to 76% over the charging period. It's just from about 02:00 to 05:30 that it only added the final 3%. So, 3% of a 14.3kWh battery (making that assumption) would be a charge rate of about 8A (if I got my maths right), which is why I suspect a trickle charge as battery get fuller.
 
Quickly checked the screen and I do now have a warning showing:

IMG_6012.jpeg
Not sure if this is linked as it may just be down to the battery dropping below 10% SOC.
 
I think it must be possible to see individual cell voltages on the display if you poke the right buttons. Hopefully you'll find one cell at a higher voltage, that has triggered the BMS to limit charge current while it tries to balance the cells.
 
@SeaGal

A normal night looks a bit more like this in terms of charging. Doesn’t look like it slows down as it gets full. Not sure if the charge limit should be fluctuating like that whilst charging or not tbf. Looking back it looks like it always has done.

IMG_6013.jpeg
 
It looks like the BMS has done 1 of 2 things :

1. Reset itself to an out of the box configuration : laptop required
2 the BMS is protecting itself due to a cell issue of sorts.

It is imperative that we exclude 2 , so please first make a screenshot of your cell voltages, then , a PC ( or Bluetooth app) will be required regardless.

Do you have the app installed on your phone ?
 
I think it must be possible to see individual cell voltages on the display if you poke the right buttons. Hopefully you'll find one cell at a higher voltage, that has triggered the BMS to limit charge current while it tries to balance the cells.
I did find the cell voltages. To me they aren’t a million miles out and nothing really stands out. It’s the v2 so no active balancing.

Cell 1 - 3220
Cell 2 - 3189
Cell 3 - 3218
Cell 4 - 3220
Cell 5 - 3214
Cell 6 - 3204
Cell 7 - 3189
Cell 8 - 3220
Cell 9 - 3220
Cell 10 - 3192
Cell 11 - 3221
Cell 12 - 3220
 
It looks like the BMS has done 1 of 2 things :

1. Reset itself to an out of the box configuration : laptop required
2 the BMS is protecting itself due to a cell issue of sorts.

It is imperative that we exclude 2 , so please first make a screenshot of your cell voltages, then , a PC ( or Bluetooth app) will be required regardless.

Do you have the app installed on your phone ?
Just posted the voltages above in reply to another post :)

I do have the app but I can’t seem to be able to log in (unless I’m doing something wrong). It’s the EN BMS app I’m using and the admin 11111 log in doesn’t seem to be working.
 
I did find the cell voltages. To me they aren’t a million miles out and nothing really stands out. It’s the v2 so no active balancing.

Cell 1 - 3220
Cell 2 - 3189
Cell 3 - 3218
Cell 4 - 3220
Cell 5 - 3214
Cell 6 - 3204
Cell 7 - 3189
Cell 8 - 3220
Cell 9 - 3220
Cell 10 - 3192
Cell 11 - 3221
Cell 12 - 3220
They are quite far apart for 3.2v.
Can you do a charge to 100% , then take a screenshot of the cells again ?
You may be looking at a cell imbalance issue
 
Just posted the voltages above in reply to another post :)

I do have the app but I can’t seem to be able to log in (unless I’m doing something wrong). It’s the EN BMS app I’m using and the admin 11111 log in doesn’t seem to be working.
That are the only creds I know of, unless you reset them yourself
 
I haven’t used it for ages but I definitely didn’t change anything. Let me try it again and I’ll share the error message I get.
 
You could try completely disconnecting the BMS from power so that it gets a full cold restart.
I have also noticed the Seplos BMS will start charging a very depleted battery slowly until it gets to a decent point and then it will allow full charge, you may have to just leave it charging and try not to draw any loads for a while.
 
That are the only creds I know of, unless you reset them yourself
IMG_6018.png

I’m stood next to the battery but I can’t remember if I used to have to connect the phone to the battery before launching the app. I don’t think it’s appearing in the list of Bluetooth devices.

I haven’t used the app in a long time tbf so can’t remember how I used to connect it. I’m sure it was just log in and away you go.
 
View attachment 238142

I’m stood next to the battery but I can’t remember if I used to have to connect the phone to the battery before launching the app. I don’t think it’s appearing in the list of Bluetooth devices.

I haven’t used the app in a long time tbf so can’t remember how I used to connect it. I’m sure it was just log in and away you go.
May be a wrong app version..
Mine looks like this

1000023260.jpg
 
That’s definitely what mine used to look like as well. Can I just check if it’s an App Store download and if it’s ‘en BMS’ in the App Store? I think I have apps set to auto update so wonder if it’s updated at some point.
 
That’s definitely what mine used to look like as well. Can I just check if it’s an App Store download and if it’s ‘en BMS’ in the App Store? I think I have apps set to auto update so wonder if it’s updated at some point.
Don't use the app store, and remove this one completely, looks like a password grabbing fake copy

Download it directly from the seplos site
BMS tools V2 is what you are looking for
 
And to give you an idea..
This is what my minimal and maximal voltage look like at about the same voltage as yours1000023261.jpg
 
And to give you an idea..
This is what my minimal and maximal voltage look like at about the same voltage as yoursView attachment 238147
I don’t think the iPhone version can be downloaded from the Seplos site, think it can only come from the App Store.

I’ll double check though but I’m sure that’s what I found when I downloaded it previously. It defiantly worked when I first got it. The screenshots on the App Store show it with the same logo as you have but it looks like the iPhone app was updated 4 months ago which may be when the logo changed.

I will check though. On the voltages with mine being from 3221 to 3189, do you think that’s a big enough gap to cause the issue? I was expecting one to be miles out if that was the problem.
 
I don’t think the iPhone version can be downloaded from the Seplos site, think it can only come from the App Store.

I’ll double check though but I’m sure that’s what I found when I downloaded it previously. It defiantly worked when I first got it. The screenshots on the App Store show it with the same logo as you have but it looks like the iPhone app was updated 4 months ago which may be when the logo changed.

I will check though. On the voltages with mine being from 3221 to 3189, do you think that’s a big enough gap to cause the issue? I was expecting one to be miles out if that was the problem.
I think as soon as you get above 3.48 , the difference is going to be huge to be honest, and yes this could def be your issue.

Did you top balance your cells before you put them in your mason ?
Where did you get and what cells are you using ?

And as to iphone...
Apples are for eating, I steer clear from electronics posing as fruits
 

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