The particular regulations, in the UK, regarding the inverter are the recently updated ESS for PEI. Electricity storage systems for prosumer electrical installations.
I'm sure you guys are somewhat familiar with how these BS standards go. They go to the N'th detail on every aspect of safety. Then they go and consult with engineers in the industry. Instead they seem to speak to product sales people who when asked their profressional engineering recommendations just copy and paste the specs from the latest, greatest, most expensive product. (licking their lips and rubbing their hands at all the people who will suddenly be forced to buy from them).
The amount of details is highlighted in the test and compliance certificates they want for LFP cells. They want tests showing individual cells have been tested with a 0.38Ohm short, having a 9.1Kg hammer dropped on them, being dropped from 1.5m onto a corner and so forth. Basically a copy and paste of a spec sheet for an automotive grade cell sold by which ever commercial outfit did the consulting.
The worst bit is. The scope of the regulations shifted from "roof top solar" and "grid tie" inverters to include any and all energy storage systems whether they feed in or not, regardless of voltage, power, AC or DC. They are ALL covered.
My basic questions was, given my limited installation purpose, how much of it applies to me? What do I NEED to do, such that I don't get ripped off paying for an OTT install I don't need.
This goes off the rails because the inverter I am installing is part of a range which, can, technically be configured to "feed out" the AC IN. I am still left unsure if this is or is not the case. The inverter is part of a large range of inverters which go from 12V/500W up to 48V/5000W and parallel and series way up further. Some units are designed for caravans and some for full rooftop solar rigs.
The documentation in question is a £70 publication. I have found the DNO copies and the government EREC reviews. The regulations covers a VAST scope of installations from single electric cars all the way up to 5MW CCGT plants. Of course it's a tedious tome of forward and backward references. "Given Annex A.2 exclusions under part 4.3.2, 5.4.6 and 7.2.9...." and things like that. They are 300+ page documents. It is very difficult to extract out the simple question "What does and does not apply to me exactly?"
"Seek professional help."
I tried this.
Solar installer: "We only do full package deals.", "We don't install customer purchased equipment", "We only provide out own equipment", "We don't do DC/Storage/Off-Grid".
Local Sparks: "Don't touch solar", "Don't touch DC", "Not qualified", "No idea mate.", "Not interested.", "£3000", "6 months at least mate I'm booked out by the solar installers"
So I need to come part way out to find WHAT exactly I need. Then I can approach more local sparks, show them the documentation etc. and be able to explain in their language what I need and what I DONT need.
The worst case is, I find a spark to do this, but he wants to do it, 110% to code and won't accept the current aged house electrical system as a start point. I'll be on the hook for a complete consumer unit update, meter board rewire and probably a few earthing tails/bonding replaced or put in place in the first instance. That all does need done. However I do not want to couple the two projects. I basically want to treat the inverter/batteries like an RV/Caravan/Motorhome/boat. The only difference is the fixed earthing.
It was that later point, "earthing". Once you touch that stuff on these forums the sparks get really upset. I'm not saying that I have a full understanding of building earthing, DNO earthing, TT/TN-S/TT-NS etc. etc. Single earth versus multiple earth and soil ohm-age considerations etc. Mine field (pun?). I figure they get so upset if you ask questions about this because 99% of them don't have a clue either, they work by the rules of thumb that got them through their tech course exams and only do their homework and sums for particular high profile jobs. "So how DARE you try and understand something that I as a 20 year professional can't understand."
In my case, one of them said I needed a separate earth for the island side of the inverter. I took this to mean a TT arrangement with house and complained that was not ideal for safety reasons and ground currents flowing between devices on different phases. BOOM! That set a few red facers off. The original "nice" spark thankfully explained it is because the island cannot "rely" on the DNO earth during a grid fault. Both earths can be bonded, but there must be a local ground rod. Also a spark should be able to tell me if I do indeed have a buried lead cable install, which changes things a little in my favour.