Solis RAI-3K 5G

[Kenny000666]

My understanding (I’m not an electrician) any consumer unit that is in an outbuilding attached to the house or inside a house (essentially has an impact to a domestic dwelling if it combusts) must be made of non combustible material.

An outbuilding like shed or a cabin that’s a distance away from the house is exempt (can’t remember the distance) if it’s non domestic. So if it goes up in flames over night, it doesn’t cause a risk of life?

My garage is attached to my house, so yes, I brought a metal consumer unit.

The smart meter isn’t exactly doing a job as a consumer unit (ie it’s not distributing power) so it’s fine if it’s made of plastic (although it’s super flimsy).

[Stinsy]

You've missed the definition of "Similar switchgear assemblies". It

Similar switchgear assemblies
The phrase ‘similar switchgear assemblies’ in Regulation 421.1.201 means those assemblies used for the same fundamental application as a consumer unit. A consumer unit is defined in Part 2 of BS 7671:

‘Consumer unit(may also be known as a consumer control unit or electricity control unit). A particular type of distribution board comprising a type-tested co-ordinated assembly for the control and distribution of electrical energy, principally in domestic premises, incorporating manual means of double-pole isolation on the incoming circuit(s) and an assembly of one or more fuses, circuit-breakers, residual current operated devices or signalling and other devices proven during the type-test of the assembly as suitable for such use.’

An example of a similar switchgear assembly is a three-phase distribution board that is intended to be operated by ordinary persons. This would have to have isolation that interrupts the three incoming line conductors and the neutral, rather than just double-pole isolation as mentioned in the above definition.

By All means fit a non-combustable enclosure. However the reason they are still sold is that they are not required if it isn't a CU!

Not sure how on earth you can say they are "not required" when it appears that the regulations mandate that they are required! Wriggling around to subvert an obvious safety requirement by a bit of dubious interpretation of the actual words seems unwise, especially as there is no cost penalty involved. The steel enclosures aren't much different in price to the plastic ones.

The critical bit is the terminations as a cause of possible fire, I believe, so it makes complete sense for ANY switchgear assembly that includes wire terminations to be in a fire resistant enclosure if it is inside. Arguably it makes sense to use a fire resistant enclosure anywhere, really.

I had this discussion with the electrician that fitted a small enclosure in our meter box, years ago, to house the fuse and RCD. He used a steel enclosure, even though the regulation quoted above hadn't yet come into force, as he said that it made sense to bring the installation up to the fire resistance standards that would be required in a year or so's time.

I'm just telling you what the rules are! In fact I explained the absurdity of them in an earlier post. Don't shoot me!

[Oldgreybeard]

Isn't the issue mostly to do with the terminals, though?

The IET article seems to suggest that it is terminals that are the cause of heat build up and fire risk, and that led to the change in the regulations, so anything that has terminals that are carrying significant current would seem to pose a potential risk. Clearly the consumer unit is a bigger risk, as the current through the main switch may be quite high, but equally the terminals on a meter for a PV system could very easily be carrying a high current as well. It's not unusual for the terminals for the meter on our PV system to be carrying well over 20A for hours on end, for example.

[Umski]

The smart meter isn’t exactly doing a job as a consumer unit (ie it’s not distributing power) so it’s fine if it’s made of plastic (although it’s super flimsy).

Exactly, the Acrel is just a meter that happens to have a mains input - it is not switchgear falling under the logic for a metal enclosure - I think this thread is drifting a little elsewhere but nice to have some thoughts on the topic I will however get a metal enclosure for my DC isolator as if anything this has the higher risk shifting several 10s of Amps back and forth!

[marshman]

Totally agree that it is the terminals that are usually the problem, (with the exception of the saga of dodgy Wylex and Crabtree MCB's a few years back). However the original question re: enclosures was for the "Acrel" meter for use with the Solis inverter. This uses a CT clipped around one of the incoming tails and a mains feed which is used to poser the meter and provide a phase and voltage reference for the power "calculation". There is no "heavy" current involved as there is with the Total Generation Meter. In that one instance ( Acrel power meter for the Solis inverter) a "plastic" enclosure will be fine - and legal.

[Umski]

Small update and a hurdle as I had expected with using the Solis (i.e. crap documentation that is contradictory in places such as the references to DRM and the CT clamps!) - I have the DC side all sorted now (with my lead acids) and was going through the set up which is fine via the rather limited inverter LCD - I had optimistically thought that using the Solis Techview app I could manage that via their app, but whilst I can connect to the access point the Solis creates using the password solis100, the 'installer' and 'advanced user' password on the app itself remains a mystery - I can't find any reference to this anywhere which is annoying as it would be nice to be able to make those changes remotely rather than in the garage. I may resort to calling their support line unless anyone has any experience of this?

[As an aside I don't know but think it's weird that I would need the data logging stick in order to do this - after all I can access the inverter settings directly but not via the AP connection]

[Moxi]

Umski,

If you get the answer to the techview app password please let me know as I have the same problem trying to access it - if i get a response to my enquiry with them I will let you know.

Moxi

[Umski]

Well the plot thickens. As if the annoying TechView app was the biggest issue, it seems not. So now everything is hooked up, no problem there, it sees the batteries, it sees the mains, it sees the CT and the meter but refuses the contribute to the house load - it has been charging the batteries but I think in a float state rather than bulk charge (they were fully charged already), however at night (no PV recorded), it sits there doing nothing, and if anything periodically drawing current from the grid (I am monitoring using open energy monitor but am yet to update the code to add a CT for the Solis branch to measure charge/discharge).

So here are some puzzlements that might help as the settings are a little bizarre:

I set up the batteries as per the 'Battery Select' menu and set the various volts/currents etc

I changed the Storage Energy Set>CT Install to PV Inverter (rather than grid) - this makes sense as it is clamped around the PV leg (though it overreads it seems) - the CT is directional and I have double checked this

Stg Mode Select>Self use - but has a hidden menu that allows access to the 'time of use' settings - so I disabled 'charge from grid', again no difference

Export Power Set>
EPM>On (export power management)
Backflow power (set to 0000W)
Failsafe>On (to comply with G100

So I can't figure out if it's due to me using Lead Acid batteries or that the way it is calculating the net power that the house is using is inaccurate - the Acrel meter seems to be pretty close to the nearest few Watts (again double checked orientation), but when I look in Information>System Info menu the 'grid power' doesn't seem to make sense - I would have assumed that it is using this value to figure out how much power to output...but it's not clear if a positive or negative value indicates import or export?

I know there's not much on Solis within this community but if there is anything anyone can add/suggest it would be gratefully received - next step will be the DIYSolar forums where there are a few discussions on the hybrid line...then Solis support (not holding breath!)

[Moxi]

You have got it set to self-consumption mode haven't you?

Moxi

[Umski]

You have got it set to self-consumption mode haven't you?

Moxi

Yep, that's the default but also double checked this hence discovering the 'hidden' time of use sub menu within self use once you select it