Isolating inverter for (other) electrical work

I have a hybrid gen-3 inverter (+solar + battery), with no EPS backup configured. I'm (finally) getting an EV chargepoint installed (not the GE one), so obviously need to make the wiring safe to work on.

Once the grid connection is cut, ISTR the inverter detects the loss of power and would stop producing AC output anyway, such as for a power cut. (But can continue to charge battery from solar ?) But for safety, I'd obviously also turn off the AC isolator. And, for good measure, may as well flip the switch in the dedicated consumer unit. [probably a good time to test RCDs, while I'm at it.] Is that sufficient ? There's no software shutdown I need to do? (Portal has a reboot button, but no power down that I can see.)

There is a rotary switch on the underside of the inverver, but
https://wiki.terravolt.co.uk/docs/inverter-shutdown-procedure/
suggests it's for the panels.

The isolation gude I was given also talks about isolating the DC connection to the panels, but I assume that's only needed for working on the inverter itself.

DD
I have a gen 1 hybrid, so might be slightly different to your gen 3, but..

you should turn the DC isolator off for the panels first to cut the DC going in to the inverter. There should be a separate (mine is black) isolator for this. If you don't do this when turning off the inverter or cutting the power to it, you risk damaging the inverter if its operating at the time (i.e. converting DC to AC). Mine has a warning sticker 'isolate PV if inverter is under load' or something like that.
Of course you could wait for it to go dark as an alternative !

The correct sequence is page 10 of the manual: https://kb.givenergy.cloud/article.php?id=84

I just use the portal > remote control > Inverter Max Output power to 0.
This soft kills PV and Battery before flicking isolators off so not so harsh on the contacts.
Don't forget to turn it back up to 100 though when your wondering why its idle when you switch it all back on!

geoffreycoan Thanks - didn't ocurr to me to look for installation manual.

The printout I was given definitely said AC before DC (but I'll double-check tomorrow). The inverter would presumably also operate from battery after cutting off the solar, so could still be generating AC. My plan had been to make sure there was plenty of room in the battery, and then when the chap arrives (unfortunately around midday) it shouldn't be generating much AC. Oh, I guess if I turn off the house consumer unit first, that should mean the inverter has no reason to be exporting anyway. (It's a pity the 'battery first' option on output priority doesn't appear to work.)

Installer manual says "You must install a separate AC circuit-breaker per inverter in order to ensure that it is adequately protected and can be safely disconnected under load" (my emphasis).

It gives the shutdown procedure as turning off battery, then AC, then PV switch. (Not the reverse of startup procedure....)

I had been hoping to keep the panels charging the battery through the inverter, as if during a power cut. Perhaps I'm just asking too much.

geoffreycoan I have a gen 1 hybrid, so might be slightly different to your gen 3, but..

you should turn the DC isolator off for the panels first

I've just had a look at the gen-1 installation manual, and it seems to disagree: p11 says turn off battery, then disconnect AC, then turn off PV switch ..?

DD That's correct.

Not sure where geoffreycoan got the idea that turning the PV array off first (when its possibly under load) at the isolator was the right way of doing things as it doesn't say that in the link he provided.

Flipping the PV isolators off when the array is under load is something you should NEVER do.

Vestas Not sure where geoffreycoan got the idea that turning the PV array off first (when its possibly under load) at the isolator was the right way of doing things as it doesn't say that in the link he provided.

Flipping the PV isolators off when the array is under load is something you should NEVER do.

That's why I pointed to the installation manual for the sequence to follow rather than risk me getting it wrong.

Follow the manual, don't listen to what random people on forum's say!

I just checked and the Gen 3 manual https://kb.givenergy.cloud/article.php?id=84 and Gen 1 manual https://kb.givenergy.cloud/article.php?id=125 both have the same sequence of steps.
Think I'll write it out and stick it to my inverter for next time.

And DD if you want to keep charging the batteries from solar whilst the grid is disconnected from the hybrid inverter, you can do. Just don't turnoff the PV and it will continue to charge OK.

geoffreycoan I have it stuck on top of the battery (under the inverter) 🙂

Page 27 of the installer training manual has a nice picture of the shutdown procedure. Installer training manual is here - https://kb.givenergy.cloud/article.php?id=76&oid=1

My installer left a Schematic of the system complete with a Shutdown / Startup flowchart. They also made an excellent job of labelling everything. I have a copy of the Shutdown / Startup sheet on top of my AIO. I haven't felt in necessary to laminate it and chain it to the kit, having worked on Plant and Equipment before retirement I know that the documentation is the first thing to take a walk...

I made up my own copy extracted from the manual today. Will stick it to the inverter so I don't forget next time.

@Tenkaykev lucky you with your installer, nothing like that from mine. Mind the AIO is a more complex beast than hybrid inverters, but my handover pack was nowhere near that detailed. Hey ho

Tenkaykev
I'd love to have a copy of the flowchart, if you wouldn't mind sharing?

Here's a copy of the Hybrid inverter 1-pager shutdown and startup sequence from out of the manual if anyone wants to use it https://docs.google.com/document/d/15sl-FtxS-FNL3QMvwxZy78gJANqiK0IQGmV9BQUerEQ

geoffreycoan
It came in really handy. Octopus came to fit my Smart Meter and due to an issue with old cables only fitted the new Gas Meter. It was a couple of weeks after my SolarPV / AIO install that they returned to fit the Smart Electric Meter. The guy who looked in the Meter cupboard looked a bit puzzled, he'd been expecting a routine install. I handed him a copy of the schematic and he said " Brilliant! "

Tenkaykev Great news

BUT

If they disconnect your EM115 energy clamps, MAKE SURE THEY PUT THEM BACK THE RIGHT WAY ROUND.

We had an Eon engineer who did a lovely job of tidying up the "organic" wiring mess in our meter box, he took photos of where the EM115's were connected so he put them back in the right place, but he put them on upside down.
Its elsewhere on the forum my experience of this, but basically anything you export gets treated as import so when this happened, the next sunny day my inverter kept discharging the battery to meet the phantom import load. End result=empty batteries.
It was only on day 2 of this happening when I was wondering why my load was so high all of a sudden that I guessed what might have happened. Simple job to unclip and reposition the clamps the right way round, and instant fix.

PianSom
I'd be delighted to if it is relevant to your install. I have a Solis 5kW solar inverter and a Givenergy AIO with Gateway. Just off out, but if it is of interest I can send it tomorrow.

Tenkaykev
Mine is a Growatt 6kW (plus AIO) but I’m sure I can adapt yours.

Thanks!

geoffreycoan
Everything has been tickety -boo since so the guy did an excellent job. My Electricity bill for December with two weeks on Flux and two weeks on Agile, next to no Solar, was -£6.00 ( they paid me )

geoffreycoan And DD if you want to keep charging the batteries from solar whilst the grid is disconnected from the hybrid inverter, you can do. Just don't turnoff the PV and it will continue to charge OK.

As it turned out, I had no say in the matter - the zappi installer clearly knew the procedure, and just did the full shutdown himself, PV and all. [Though not the battery...] Fortunately, I'd reduced the inverter max power down to 0% as above when going round the house turning things off, so there shouldn't have been much activity anyway. And power was only off for a few minutes anyway...

Tenkaykev if it is of interest I can send it tomorrow.

Just a small nudge! 🙂

PianSom

Tenkaykev
Thank you!

A bit more complex than my installation - I don't have a non-maintained consumer unit. But interesting - thanks again

Tenkaykev Everything has been tickety -boo since so the guy did an excellent job. My Electricity bill for December with two weeks on Flux and two weeks on Agile, next to no Solar, was -£6.00 ( they paid me )

That's an excellent result.

Looking at my figures in Home Assistant (which take account of the Octopus free power-up events but not the Demand Flexibility Savings of _£50), my bill will be about £195. But that includes all the heating as well through the ASHP, about 60% of my total import.

You timed your move to agile well, avoided the 60-65p slot prices we had in early December.

Gotta take the rough with the smooth ...

geoffreycoan I think these systems should come with little stickers you can slap on for right direction or at least have arrows hard painted/imprinted in red.

Jellybaby There is an arrow pointing K to L on the CT clamp, but different versions of the GivEnergy installation manual diagrams are inconsistent about which way they should point (I wrote about this elsewhere on the forum).
Good idea though, I'll go and draw an arrow on mine just in case for the future