@transparent it’s resided in a cupboard for about 4 years, delayed when my roof came off and a home rebuild.  She had my ears bleeding and reluctantly I fitted it having to reinforce the ceiling. It has a built in transformer and not a driver like that white one. I would have to take it down to inspect it and that’s not happening, I nearly had a stroke getting it up there. But I read that these 10 watt halogen bulbs can draw .8 of an amp 24 of them is a lot and to be honest this amount of heat surely can’t be complient.  All my warning bells were going when we first installed it and when my daughter fitted the bulbs. The thing shut down and when I felt the heat I thought a thermal cut out on the transformer. Sure as I thought it came back on once cooled.  Monitoring it it then started popping the 6amp breaker.  I don’t know how to work out the draw on the circuit from a transformer light, it must be on the lamp somewhere but the transformer should be able to manage the load. I thought fitting led bulbs but firstly not sure if the lamp will have a driver suitable and lastly that the lamp is unsafe.  I opted to disconnect it. That heat rises and those steel cables were too hot to touch, I never checked the mount which housed the transformer but it must be Chinese junk. She purchased a lamp before which I refused to fit and chucked it in the bin.

@transparent I'm also considering the DIY installation route and hope you don't mind me jumping in?

We already have 4.32 installed at the same time the ashp (2 x 10kw grant) on a separate (non hybrid solax) inverter.

Recently had 3 phase installed and decided to get 2  10kw batteries to a new 3phase Sunsynk 10kw inverter.

I'm thinking of a further 12-16 panels (to equal 10kw) but want to go the DIY route as it would save substantially on costs.

1. Would this be doable?

2. Do I need DNO application for this if on 3 phase/ have the inverter already installed

3.They would have to MCS certified for the export (although my intention is to keep the batteries topped up and trickle feed the hot water cylinder/ev)

4. And could I ask you for further advice if I go this way 😁 re rail installation or do you have a separate thread or web page

@bretix octopus do a thing called an Eddi that feeds the surplus into both your heating and hot water cylinder.   I’m sure the max you can generate is 4kwp before getting permission and you have to be a registered installer for some of it. Octopus wouldn’t sell me the Eddi and want 600 quid to install.  But the real experts will be along soon.

Great questions @bretix  and extremely wide in their scope.
We will have to explore these avenues in a number of steps because there's not enough hours in the day to answer all this in one go.

1. Everything is doable...
... unless you attempt to break the 2nd Law of Thermodynamics.

That's where we have to draw the line I'm afraid.

2. You require G98 and G99 consent from your DNO for devices that export to the grid.

Adding an inverter would therefore require a further G99 Application,
whereas merely adding solar panels would not.

2a. Let's assume that your original Solax inverter was professionally installed and that the Installer correctly applied for G98 consent.
That means:

• the inverter is single-phase, because you didn't have 3-phase at the time
• its maximum export is 16A, which equates to 3.68kW
• that model of Solax already had G98 certification and was on the Approved List held by the Electrical Networks Association (ENA)

It isn't relevant that you had 4.32kW of PV panels connected.
That simply allowed the inverter to handle more energy on overcast days.
On days with full sun any generation above 3.68kW wouldn't have been accepted by the inverter. That's OK.

2b. I understand the operation of a Sunsynk 3-phase inverter. Is that model number SYNK-10k-SG04LP3?

Do we assume that the original Solax is still connected to one of those phases?

What are those two batteries?
Is each of them 10kWh capacity?
Are they connected to the Sunsynk inverter in parallel?

A photo would help! 😎 

3. If that Sunsynk inverter has been installed by an MCS-accredited company, then you already have an MCS number for that, don't you?

Ditto for the original Solax inverter and its solar panels.

That means you can already use those numbers to obtain income for any electricity which is exported.
So how would your Energy Supplier know whether you added any more PV panels to your roof?
Why would those additional solar panels require yet another MCS number?

You can't add solar panels on a DIY basis and obtain an MCS number for them.
MCS numbers are only available through MCS-accredited installers because they have access to the MCS online forms.

Let's stop there and await your reply.

@transparent might have to consider weight as well, that’s a load of panels, with things like wind loading and possible snow on the roof

Posted by: @david999

↑

I don’t know how to work out the draw on the circuit from a transformer light

A standard wire-wound transformer will be at least 90% efficient, even if the coils have been hand-wound by a blind-man with three fingers missing.

24 bulbs rated at 10w each comes to 240w

Let's increase that to 260w to account for the transformer's contribution to global-warming.

On the mains side, the chandelier will draw a current of 260/240 where the 240 is mains voltage.
That comes to 1.08 Amps.

Is the trip which blew an MCB or an RCBO with a small push-to-test button?

The efficiency of a light requires us to know the light output in lumens.

Nowadays it would be a poor LED if it was rated at less than 100-lumens per watt of input power.

The Building Regulations Part-L define a standard.
But it's overly complex because it considers only the main light sources in a room, not plug-in side lights, and there's an average taken across the light fittings on a single circuit.

The simplified form of Part-L is that each main light must deliver a minimum of 75 lumens/watt.

Regardless of how efficient the light output is from that chandelier, trips blow for a reason...
... and that reason is safety-related.

Your daughter's house insurer would be very unhappy if that chandelier remained fitted!

Posted by: @david999

↑

might have to consider weight as well, that’s a load of panels, with things like wind loading and possible snow on the roof

Yes, we can come to loading factors and wind-lift later.

That's substantially down to the choice of mounting rails and the rafters which the roof-brackets get screwed to.

I have the Span Tables from Part-A of the building regs, but I think we're still several steps back from that 😉 

Here's my own roof, which has an interesting mix of rafters from the original 1937 farmhouse, and the Glulam beams I installed for the contemporary extension to the south and west:

I couldn't comply with the MCS specifications for roof-brackets anyway.
Mine is a warm-roof construction, so the MCS-approved 80mm stainless steel bolts wouldn't have penetrated the insulation layer to reach the rafters below!

@transparent it’s an mcb, and I think it’s more to do with these halogen bulbs, meant to be 10 watts but they present more like mini heaters. It’s disabled at the minute until I figure out what the issue is. My next step would be to try led bulbs if they work but only after I check out where she got it from.  Went up to do a couple of jobs for her and three weeks later just finished, but she stays on her own with the little one so I need to help out. Burning her house down not a good idea though, although I just fitted smoke alarms to all the rooms last week since just too much electrical items in rooms from when I was a lad. 

i notice from your photo you have solar tubes, mine is a 20 tube navitron and I need two tubes for it but nobody will post.  Any ideas on a way around this short of travelling myself. 

@david999 - Irrespective of the number of other lights also connected to that 6A MCB, if it's tripping only when the chandelier is getting hot then it's almost certainly due to thermal breakdown of the insulation around the conductors.

Before disposing of it, please apply a lump hammer to the enclosed transformer.
That will prevent a worker at a recycling plant attempting to do what he's paid to do by sending it to a 'repair and resell' centre!

I don't know what type are the 10W filament bulbs in that chandelier, but I wouldn't advise sourcing LED equivalents if the 12v transformer has already suffered insulation damage on the mains side.

One of the responsibilities of an engineer is to create the stimulating environment in which others will follow.
If your daughter hasn't picked up your skill-set, then jump a generation and buy a Meccano set for her offspring!

Solar Thermal tubes.

As you will know, Navitron itself is no longer trading.
But its products are mostly still available from some of its main installers.

As a starting point, talk to Stoves and Solar.

When I wanted two replacement tubes, I waited until they were about to start a job in Cornwall.
They put a couple of tubes in the van and we arranged a rendevous at a tourist picnic spot just off the A30.

@transparent my wife says I am too fussy and I reply with that it’s the way I am hard wired. There is only one way and that’s the correct way to the best of your ability and it keeps my conscience clear. 

Walker watts just out today after I reported the loose neutral supply cable to Scottish power.  The bloke said he had spoken to the guy who installed the three phase cable and no way he left the cable loose, not only loose but stripped the screws.  I said then you need to speak to octopus because two engineers were present including myself when the cable fell out. It’s the closest I have been to a fire and had i used the heat pump it would have burnt out the contacts and cable. My batteries and solar have been running the house so they saved the day.  But check and double check and even a final check before you leave. But they left the first time having pulled out the main feed for my solar and fitted the magnetic pickup thing on the feedback cable the wrong way. So hard to say he checked anything. Too much of a hurry to get away to sit in a van doing nothing.  Never met a bunch paid so much who were so reluctant to work. 

Regardless of who's worked on that mains supply to your house @david999 it is the property of your DNO.
They will want to know what's happened and to be assured that it's now correctly fitted, and without a cross-threaded or stripped screw.

Please download a copy of the old version of the MOCOPA Guide.

This was what Meter Operators/Installers referred to when attending on site.
It lists all possible faults with the DNO side of the installation and provides the relevant Fault Codes.

It's well written, clear, copiously illustrated and invaluable.

It's been replaced by text-based Regulatory Notices held in the RECC Library.
Their strategy is legalistic and intended to show who's at fault when something has gone wrong.
I despair of that approach!

Please forward that old MOCOPA Guide PDF to any other relevant people you know who might ever come across a mains incomer in a questionable state.

I've previously supplied copies to Home Energy Advisors, Social Workers and a District Nurse.

@david999 Never has so much danger been caused for so little effort by so few (Sorry Winston Churchill.)