Battery Problem with solar immersion controller and battery system.

[Deleted member 110823]

Hello professionals out there! This is my first question on this forum.
I am not a professional and have no electrical qualifications.
I have a PV and battery system. The battery was installed in 2016 and is still under guarantee. It is a Samsung 3.6 KW in the A10 series. Samsung have now stopped that side of their business and have passed it over to Hansol (who apparently made the thing for Samsung in the first place). It was installed by Avonside Eco Homes, which was a subsidiary of Avonside Roofing, but is no longer trading.
Recently, the battery system has started randomly shutting itself down. Switching it off at the main isolator and on again resets it, when it will run again for random amounts of time - it could be a minute or two, or some hours or even all day.
I contacted Hansol's service department, who monitored it remotely through its internet connection and said that over-voltage on the grid was causing it to trip. They said it is set to trip in excess of 253 volts. I contacted Western Power Distribution, who thought this unlikely, but fitted a monitor to record voltages continuously for a week. During that time the A10 continued to trip randomly, but the grid voltage never went higher than 245.8.
In the meantime, I had noticed that the system only tripped when the Immersion controller was set to automatic. Ours is an Absolute Energy Master, and was installed by Avonside as part of the package that came with the battery. I pointed this out to Hansol, who said that they didn't know what that was (although I told them) but that the A10 is not designed to run with one. Absolute Energy have now gone out of business, so I cannot pursue that line. Avonside now have nothing to do with batteries, only PV panels, and Avonside Eco Homes no longer exists, so no joy there either.
My suspicion is that the immersion controller is not to blame, as I have two - the other is running a heater in the hall (only used in winter, when the hot water is produced by a back boiler in an Aga, which we turn off in summer and use an immersion heater). I have tested the second one, and the A10 trips randomly with that too. It seems unlikely that both would fail in the same way at the same time. Also, much more recently I have noticed that if I don't switch the immersion controller on (i.e. to automatic) until the battery is nearly fully charged (85% or more), then the system does not trip, but works perfectly, with current fluctuating correctly with the level of sunlight and other appliances being used.
So, if anyone has managed to plough their way through this and got to this point, do you have any ideas about what the cause of this might be and whether I can get anything done about it?

 

[Wilko]

Hi - thanks for confirming that manual operation of the immersion heater does not make the A10 trip. Along the lines of #20 can you confirm it never trips with the immersion controller switched off? Perhaps it is seeing an overload when trying to balance sending power to the battery or the grid and immersion controller winding the load up and down in accord with its own programme (?). As you say, if immersion is left on 100%, the system does not trip.

 

[Deleted member 110823]

You have given me a clue. I checked the positioning of the current transformers (thanks for telling me what they're really called) and moved the export one. You say you would expect it to be on a negative cable, the diagram in the Energy Master installation guide shows it should be on the positive. I have moved it from the positive to the negative, and thought that had fixed the problem - but then it tripped. Even so, it has been more stable today than many other days. Could it be that simple??
I have to go out now, but will try and answer your other questions later.

 

[marconi]

Re #22. Please take a look at Figure 2 of:

https://midsummerwholesale.co.uk/pdfs/Solar-Cache-Installation-guide.pdf

You will see the positions of 2 current transformers. One (shown on the left of Fig 2 - measures export power) clips around any one of the two thick cables 'leaving' the meter to the consumer unit. The other one (shown on the right above the Consumer Unit - measures PV generation fed into the mains wiring) clips around the line(brown) or neutral (blue) of the output from the Samsung A10. Neither current transformer is clipped around the cables (positive and negative) between the solar panels and the A10.

Now, if you a current transformer clipped around one of the PV panel cables this is wrong. To move it to clip around the Samsung A10 line or neutral output will require an electrician to do it safely.

Please confirm you have an mcb in the CU for the PV.

 

[Deleted member 110823]

Hi - thanks for confirming that manual operation of the immersion heater does not make the A10 trip. Along the lines of #20 can you confirm it never trips with the immersion controller switched off? Perhaps it is seeing an overload when trying to balance sending power to the battery or the grid and immersion controller winding the load up and down in accord with its own programme (?). As you say, if immersion is left on 100%, the system does not trip.

Yes, I can confirm that it only trips when the controller is set to automatic. You may be right about balancing sending power to the battery or elsewhere, but I'd have thought if that was the case it might trip when charging and, say, you turn on the kettle. Other things turning on or off round the house have never been a problem.

 

[Wilko]

Re the kettle : If I've understood correctly the immersion controller (when on auto) is continuously fiddling the current to the immersion and the A10 may trip. And when immersion is manually on or off the A10 behaves normally. I think the kettle on or off is same as immersion manually on or off. No continuous load adjustment and no A10 tripping, if that makes any sense. It's only a theory, with no data to support ...

 

[Deleted member 110823]

Re: #9. Some more questions please.

1. Your diagram shows the Samsung A10 connected by a 'T' to the tails going to the consumer unit. Is this actually so? A picture would be helpful. I'd have expected the A10 to be connected to a circuit breaker in the consumer unit.

2. Where does the thin white wire shown on the left of the Absolute go to?

3. The current transformer are the devices which clip around the cables. Are they wired or wireless? Can you take some pictures?

4. Please confirm there is a current transformer clipped on the live or neutral leaving the A10. It must not be simply connected around both live and neutral. Again a picture would be helpful.

5. There should be another current transformer connected around one of the thick cables on the house side of the meter. A photo would be helpful.

6. Where is the A10 located? Is it getting too hot during the recent very warm weather?

Sorry for the delay, also for my amateurish attempts at describing how it's all wired up. I have attached a photo - hope that helps. Sorry it's sideways.
To answer your questions in order:
1. There is a circuit breaker, but it's stand-alone, not in the main consumer unit. See photo.
2. The thin white wire is the antenna. There is one on each of the throttles and on the Energy Master control unit.
3. The current transformers are wired. You can see one in the photo. They connect to the Energy Master with phono plugs, hence the birds nest of thin black wires.
4. There is a current transformer clipped on the live wire leaving the A10. It is just out of sight to the left of the system consumer unit. The electrician who installed it looped the live wire out of the side of the unit and back in again to accommodate the current transformer.
5. See 3 above.
6. The A10 is on the floor directly below the photo. It has been getting warm there, but nowhere near 40 degrees. The fans appear to be working well and run at different speeds at different times.

 

[Deleted member 110823]

Re the kettle : If I've understood correctly the immersion controller (when on auto) is continuously fiddling the current to the immersion and the A10 may trip. And when immersion is manually on or off the A10 behaves normally. I think the kettle on or off is same as immersion manually on or off. No continuous load adjustment and no A10 tripping, if that makes any sense. It's only a theory, with no data to support ...

Yes, that's right. However, when it's in the mood it can run perfectly well for hours at a time with the current fluctuating all over the place as clouds pass, the fridge goes on and off, someone uses the microwave etc etc. There seems to be no pattern to when it trips, only that it has to be set to automatic and (possibly) with the battery at a low percentage charge.

 

[marconi]

From the picture all seems connected correctly. I have exhausted the things I would have checked, albeit - clutching at straws - I'd run a calibration sequence on the immersion controllers see section 5 of

https://midsummerwholesale.co.uk/pdfs/Solar-Cache-Installation-guide.pdf

I suspect the battery or the cooling system - two sub-systems of the A10 which age with operational use.

Here is a website which might help you find a technician to attend your home:

Samsung SDI ESS Energy Solar Battery | Solar Guide - https://www.solarguide.co.uk/solar-batteries/samsung-sdi-ess-energy#/

When you discover what was the problem it would be nice if you cold report back.

 

[Deleted member 110823]

From the picture all seems connected correctly. I have exhausted the things I would have checked, albeit - clutching at straws - I'd run a calibration sequence on the immersion controllers see section 5 of

https://midsummerwholesale.co.uk/pdfs/Solar-Cache-Installation-guide.pdf

I suspect the battery or the cooling system - two sub-systems of the A10 which age with operational use.

Here is a website which might help you find a technician to attend your home:

Samsung SDI ESS Energy Solar Battery | Solar Guide - https://www.solarguide.co.uk/solar-batteries/samsung-sdi-ess-energy#/

When you discover what was the problem it would be nice if you cold report back.

Just to keep in touch - Solar Guide are looking for an engineer who can come and look at my system and, I hope, diagnose the problem. So, thanks very much for their details. Fingers now crossed....