DIY Battery/Solar installation..

[Malt_Vinegar]

You don’t need an earth rod unless you want to use EPS functions. For standard grid ties systems, the existing earthing is fine.

I am using EPS with this inverter.
So looking to add a rod, following the instructions here (20 mins in)

This explained adding a rod to a TN-C-S system, if I need it

 

[Mercenary Keyboard Warrior]

Seems very cheap for an inverter that can also EPS. The EPS functionality for mine was about £500 on its own, its quite a significant upgrade cost for most systems (if they even offer it)

My understanding was that all "proper" EPS need to in effect gateway the cabling coming in so they can physically disconnect the live from the grid.
For example mine routes the tails after the main fuse into my system, then back out to the tails in for the main CU.

There are some sketchy EPS ways as well which can be physically enabled if the main grid is disabled.

Stuff moves on though so maybe its more common now than it was two year ago.

Just mentioning as I know most people I know who had solar installed just assumed it would work in a power cut.

 

[b0rn2sk8]

I am using EPS with this inverter.

Then you'll need a rod on the circuit(s) running off the EPS and you cant rely on the earth from the grid.

However, you wouldn't follow the instructions in the video unless its a whole home back up system like one that uses a 'gateway device' (like those used with GivEnergy All in One or Tesla Power Wall) that physically disconnects the house from the grid.

If you are just running a single circuit directly off the inverter like most EPS set ups, the earth rod needs to be connected to that single circuit. An earth rod for the whole installation will not protect it as the circuit is not usually connected to the rest of the installation.

 

[Ron-ski]

My understanding was that all "proper" EPS need to in effect gateway the cabling coming in so they can physically disconnect the live from the grid.
For example mine routes the tails after the main fuse into my system, then back out to the tails in for the main CU.

Just had a quick look at the data sheet, its not a proper EPS system, as per the post above, its intended to supply a critical circuit, most installers just fit a double plug socket.

 

[Ron-ski]

@Malt_Vinegar As you have a sparky onboard, this really should be left to them, I'm all for DIY'ing stuff, but certain things should be left to those qualified, and earthing can be quite complicated, and extremely important.

 

[Mercenary Keyboard Warrior]

Just had a quick look at the data sheet, its not a proper EPS system, as per the post above, its intended to supply a critical circuit, most installers just fit a double plug socket.

Yeah double plug socket is the kind of sketchiest I have heard of. Its usually the retrofit to a "but I thought I would have power in a power cut" from what I can tell.
I am sure I saw one of the solar guys saying it was against the specs (for what they are worth as we know) but could be relevant in regards insurance.

I am pretty sure when they fit a socket its manually switched on and off isn't it?
IE manually isolate inverter from the grid to in effect off grid mode and then enable the socket.

I know on my system it was capable of running one circuit (they say two at a push if you could guarantee low usage) but then I paid for the whole house EPS.
I think the plan was to do like b2sk8 said and move one circuit from the house to the inverter in effect as part of installing into the CU.

 

[Ron-ski]

Yeah double plug socket is the kind of sketchiest I have heard of

I wonder how many stick a plug on each end of a piece cable to power the house

It is surprising how many think once they have solar, or solar & batteries the power will stay on.

Reading the data sheet for the inverter it said 20ms reaction time, and as its designed for critical circuits, it would make sense they will be powered all the time, so the inverter should switch off feeding power back to the house/grid and only supply power to the critical circuit during a power cut.

 

[Mercenary Keyboard Warrior]

I wonder how many stick a plug on each end of a piece cable to power the house

It is surprising how many think once they have solar, or solar & batteries the power will stay on.

Reading the data sheet for the inverter it said 20ms reaction time, and as its designed for critical circuits, it would make sense they will be powered all the time, so the inverter should switch off feeding power back to the house/grid and only supply power to the critical circuit during a power cut.

That sounds exactly like mine was originally being installed as in that case. 1 or 2 circuits they said.
So sounds like they do have EPS now but thats going to be awkward deciding what to have.

Actually typing this its coming back to me. They said 1 or 2, but if 2 one needed to be lighting, not basically most of the house ring circuits.

 

[Ron-ski]

You and I both have whole house back up, BUT we have to manage the load during a power outage carefully, overload the inverter and it will shut down.

That wasn't too much of a problem for me with an 8kW inverter than can briefly peak higher, but with a 9.8kW induction hob being fitted, and potentially an ASHP next year, it could be very easy to overload my inverter - knew I should have gone for the bigger 12kW inverter

 

[Mercenary Keyboard Warrior]

You and I both have whole house back up, BUT we have to manage the load during a power outage carefully, overload the inverter and it will shut down.

That wasn't too much of a problem for me with an 8kW inverter than can briefly peak higher, but with a 9.8kW induction hob being fitted, and potentially an ASHP next year, it could be very easy to overload my inverter - knew I should have gone for the bigger 12kW inverter

Yeah true. I think its been super rare for me to go over 5.5kw apart from when deliberately doing so. I guess could be blips though.
9.8kw!? Thats all rings on I assume?

Should have bought a bigger boat inverter

 

[Ron-ski]

9.8kw!? Thats all rings on I assume?

Yeah, I slipped up there, we had a 900m gas hob, so needed a 900mm induction hob, not much choice. Discussed with the electrician and decided to go with a 7.2kW hob, but whilst looking I found a newer model, ex-display and less than half price, so snapped it up, only realised a couple of days ago it was 9.8kW!

Still waiting for the electrician to get back to me, I have a 10mm cable installed, and really hope I don't need to put in a 16mm cable, just depends if he needs to de-rate the cable.

See here for the hob in question.


.

 

[b0rn2sk8]

You and I both have whole house back up, BUT we have to manage the load during a power outage carefully, overload the inverter and it will shut down.

That wasn't too much of a problem for me with an 8kW inverter than can briefly peak higher, but with a 9.8kW induction hob being fitted, and potentially an ASHP next year, it could be very easy to overload my inverter - knew I should have gone for the bigger 12kW inverter

Same with me, mine is limited to 6kw unless the battery is below 80% and I also have some solar coming in. I could add another GivEnergy All In One and that would give me 12kw. If I am really honest with myself, 6kw is actually fine.

Heat pump ticks along at 500-600w most of the time and baseload is around 400w with a few lights and the TV on.

My induction job is 7.4kw but a single induction hob ring is 3.6-4kw absolutely maxed out, they are usually ticking over at well under 2kw at power 7/9, any hotter and your food us burnt and you'll quickly ruin any non-stick pans you were using because they have over heated.

I can usually run the oven, 2 hob rings, the microwave and still have enough headroom for the boiling water tap to kick on as well as my baseload in that 6kw budget. Sure I'm not turning all that on from cold at the same time and staying under 6kw but you don't tend to do that in the real world either.

 

[Ron-ski]

Sure I'm not turning all that on from cold at the same time and staying under 6kw but you don't tend to do that in the real world either.

That's what electricians refer to as diversity.

I'm sure with 8kW we'd be fine (full on sun we'd have over 11kW available), and a power cut is so rare we've not had one since I installed the system early last year.

 

[Mercenary Keyboard Warrior]

Plus if real outage your going to fairly quickly limit what your using.

 

[Mercenary Keyboard Warrior]

Ok what bugger mentioned power cuts?...

We just had one, well in reality its the 3rd micro outing in last few days.
1st took out just my chia rig
2nd earlier took out other halves laptop
3rd we just had, it managed to flip the RCD so took all sockets. Was weird having the lights on and looking out into total blackness as everyone else was in the dark

Other half is on local FB stuff and loads of people the same, plus seems to be rolling round the local area over time. So I am guessing grid guys are doing something which is probably what the first two were as well.

 

[b0rn2sk8]

Ok what bugger mentioned power cuts?...

We just had one, well in reality its the 3rd micro outing in last few days.
1st took out just my chia rig
2nd earlier took out other halves laptop
3rd we just had, it managed to flip the RCD so took all sockets. Was weird having the lights on and looking out into total blackness as everyone else was in the dark

Other half is on local FB stuff and loads of people the same, plus seems to be rolling round the local area over time. So I am guessing grid guys are doing something which is probably what the first two were as well.

We've had loads of those over the last few weeks, very annoying as my WiFi and NAS resets as the 20ms EPS isn't quite fast enough to keep them running but everything else carries on as normal. One or two of them managed to flip the main RCD CU which was even more annoying, one benefit of 17th edition is the lights were not RCD protected

 

[Mercenary Keyboard Warrior]

We've had loads of those over the last few weeks, very annoying as my WiFi and NAS resets as the 20ms EPS isn't quite fast enough to keep them running but everything else carries on as normal. One or two of them managed to flip the main RCD CU which was even more annoying, one benefit of 17th edition is the lights were not RCD protected

Your relatively local to me so probably related incidents.

 

[Ron-ski]

Ok what bugger mentioned power cuts?...

That would have been me

We've had loads of those over the last few weeks, very annoying as my WiFi and NAS resets as the 20ms EPS isn't quite fast enough to keep them running but everything else carries on as normal. One or two of them managed to flip the main RCD CU which was even more annoying, one benefit of 17th edition is the lights were not RCD protected

The Victron is so quick nothing falters, I've switched the grid off many a time, and never had an issue, although a power cut might be different to an instant switch off.

 

[Mercenary Keyboard Warrior]

That would have been me


The Victron is so quick nothing falters, I've switched the grid off many a time, and never had an issue, although a power cut might be different to an instant switch off.

Normally I dont notice anything but wonder why the cooker isnt working. The cooker clock seems to be uber sensitive for some reason
Next most sensitive is my chia farm which all runs from one 13 amp socket, but its a power monitor and remote smart switch so I think its that that is sensitive

There is building going on near me and I think thats the main cause.

 

[Malt_Vinegar]

@Ron-ski - The Solis S5-EH1P5K-L is a 5kW hybrid inverter, which is ideal for residential energy storage systems. Compatible with both lithium and lead-acid batteries, this highly efficient inverter offers uninterrupted power supply (20ms reaction) and a back-up supply to support more critical loads.

MY understanding (from the wiring diagram) is that you put stuff that cannot handle 20ms switchover onto the back-up and everything else has a "dirty" interupt, but power switches over. I have UPS on the things that could not handle it, so not going to use the backup circuit!

*edit* I stand corrected! It looks like EPS is only available IF you buy a separate module, so there is no requirement for a local earth, regardless as I will be without EPS initially, anyway