Growatt battery not discharging

[johnb2713]

Ill put £10 on the Electric Car draining the battery over night because the inverter is not transitioning into battery first mode during the charging period.

Looks like you need to raid the piggy bank and send that £10

 

[thfctom]

Looking at post #32, you need to be on load first, your inverter is exporting everything generated to the grid.

It is now, that was a strange anomoly yesterday that I haven't seen before or since.

I'm actually on battery first, which defaults to load first if we're outside the overnight window, right?

 

[johnb2713]

It is now, that was a strange anomoly yesterday that I haven't seen before or since.

I'm actually on battery first, which defaults to load first if we're outside the overnight window, right?

It should be showing load first, any excess after the load has been supported is then fed into the battery, once charged excess then goes to the grid.

 

[michael8554]

"Round grey cable (2) enters the "six holes" input. This round grey cable goes to the CT I believe - it definitely goes in that direction and connects to a black cable which I'm pretty sure is the one that leads to the CT near the meter."

If altering the CT direction made no difference to the displayed behaviour, then I'd suggest the grey-to-black cable join is faulty, or unscreened cable has been used to extend, or the run is just too long ?

 

[thfctom]

"Round grey cable (2) enters the "six holes" input. This round grey cable goes to the CT I believe - it definitely goes in that direction and connects to a black cable which I'm pretty sure is the one that leads to the CT near the meter."

If altering the CT direction made no difference to the displayed behaviour, then I'd suggest the grey-to-black cable join is faulty, or unscreened cable has been used to extend, or the run is just too long ?

Yeh potentially, I’ll have to get the installers out to look at that.

 

[thfctom]

Another weird one this morning, the system thinks we need energy from battery and solar. But it’s exporting almost all of it. House isn’t using anywhere near that amount.

 

[user 36882]

@ thfctom you are describing almost exactly same issues as I have had now for 6 months, since our battery storage was commissioned (was installed initially but it took installer a while to actually get the batteries to respond/function):

• Battery does not discharge in response to load
• 'Grid first/TOU discharge' discharges at 3kW regardless of load when we manually use that command (e.g. to use some power in evening if needed)
• App and web app no longer show grid import/export data (since battery was commissioned)
• Load consumption always matches solar production (which is just wrong, even did this when we were on holiday and house was empty!) - was 'normal' before battery was commissioned.
• Random but minimal battery discharge for short periods (not in line with load)
• Random o/night battery charging from grid (though AC charging is disabled)

I have read a couple of threads about the ec2a.v meter that is part of our installation, but tbh I don't really understand its purpose. I did read however that installations with battery require a different version / setting of this meter type, but it goes way beyond my knowledge and understanding. Could this be relevant or just a red herring?

Installer insists all is set up correctly and CT is fully functional, but he goes silent on me when I challenge on the points above, that have not changed since the battery was commissioned. It is clear however that our installation is not functioning as it is meant to.
We have Growatt 3600 hybrid inverter, PV, 2 x Growatt 6.5kW batteries (no EV charger or other complications).
All very frustrating.
@johnb2713 - thanks already for all inputs, much appreciated.

​

 

[thfctom]

@ thfctom you are describing almost exactly same issues as I have had now for 6 months, since our battery storage was commissioned (was installed initially but it took installer a while to actually get the batteries to respond/function):

• Battery does not discharge in response to load
• 'Grid first/TOU discharge' discharges at 3kW regardless of load when we manually use that command (e.g. to use some power in evening if needed)
• App and web app no longer show grid import/export data (since battery was commissioned)
• Load consumption always matches solar production (which is just wrong, even did this when we were on holiday and house was empty!) - was 'normal' before battery was commissioned.
• Random but minimal battery discharge for short periods (not in line with load)
• Random o/night battery charging from grid (though AC charging is disabled)

I have read a couple of threads about the ec2a.v meter that is part of our installation, but tbh I don't really understand its purpose. I did read however that installations with battery require a different version / setting of this meter type, but it goes way beyond my knowledge and understanding. Could this be relevant or just a red herring?

Installer insists all is set up correctly and CT is fully functional, but he goes silent on me when I challenge on the points above, that have not changed since the battery was commissioned. It is clear however that our installation is not functioning as it is meant to.
We have Growatt 3600 hybrid inverter, PV, 2 x Growatt 6.5kW batteries (no EV charger or other complications).
All very frustrating.
@johnb2713 - thanks already for all inputs, much appreciated.

​

I've had to set my load-first discharge to 90%, to stop it needlessly discharging the battery today. It'll be interesting to see what it does when I turn it back to 5% when the sun goes down later.

I say interesting, I think I'm losing my mind here!

I have the installers getting back to me on Monday, will update this thread then, as well as if anything else weird pops up.

And I agree, thanks @johnb2713 for your help so far!

 

[johnb2713]

Another weird one this morning, the system thinks we need energy from battery and solar. But it’s exporting almost all of it. House isn’t using anywhere near that amount.

The fact that your smartmeter shows the export taking place but the inverter thinks it's feeding the house suggests to me the CT is the wrong way round.

 

[thfctom]

The fact that your smartmeter shows the export taking place but the inverter thinks it's feeding the house suggests to me the CT is the wrong way round.

That would make sense, but this picture shows when I open it, this is the way round it is assembled (see arrow points away from meter).

It’s clipped onto the furthest right live grey wire (brown cap).

 

[johnb2713]

That would make sense, but this picture shows when I open it, this is the way round it is assembled (see arrow points away from meter).

It’s clipped onto the furthest right live grey wire (brown cap).

If the installers reversed the connections at the inverter end the arrow would need to point the opposite way.

 

[thfctom]

If the installers reversed the connections at the inverter end the arrow would need to point the opposite way.

Are the connections reversed at the inverter end? How would I tell that?

Also, just realised I uploaded a very blurry and useless image!

 

[thfctom]

Swapped the CT direction round, put the discharge stop back to 10%, and it's still being silly, thinking the house is using more than the solar can generate.

 

[bladerunnerpv]

Swapped the CT direction round, put the discharge stop back to 10%, and it's still being silly, thinking the house is using more than the solar can generate.

(Consumption + export)=(pv generation + battery discharge)

Consumption > solar, so it's using some battery to supplement?

It could be drawing from grid to fill the gap, but it's using battery instead so saving money.

I've not re-read the whole thread, am I missing something?

 

[thfctom]

(Consumption + export)=(pv generation + battery discharge)
Job done?

If the consumption was correct, but it's not!

At the point of that screenshot, only the fridge/freezer and a few standby items were on. Should be <200W. Not >3kW.

Smart meter was saying it was exporting nearly 3kW.

 

[bladerunnerpv]

Ahh! Apologies!

At least one of pv and smart meter must be wrong....

I appreciate this is probably too much hassle to check, but to help fault finding, it's often useful take it down to the simplest level and remove as many variables as possible. What happens if you turn the pv system off completely? Does the smart meter reading make any sense then? Give it time to settle, then switch a toaster or kettle on. Does smart meter reading make sense then too?

Taking it to the extreme, what does smart meter read if the mains at the consumer and the pv system is switched off?

I don't have a smart meter fitted in my house, so forgive the daft question. Is there a display in the meter cupboard, does it tie up with the smart meter display unit wherever that is inside the house?

 

[bladerunnerpv]

From what I've read on the forum there should be a procedure for safe shutdown and restart of the pv system which the installers should have informed you of.

 

[johnb2713]

If the consumption was correct, but it's not!

At the point of that screenshot, only the fridge/freezer and a few standby items were on. Should be <200W. Not >3kW.

Smart meter was saying it was exporting nearly 3kW.

There has to be something wrong with the CT, it's cabling or the connection. Turning it round hasnt changed anything.

 

[thfctom]

From what I've read on the forum there should be a procedure for safe shutdown and restart of the pv system which the installers should have informed you of.

I never got informed of this, but will take your suggestions to them when I have a call with them on Monday. Cheers!

 

[thfctom]

There has to be something wrong with the CT, it's cabling or the connection. Turning it round hasnt changed anything.

I agree, will try to see if they can replace.