Need help regarding the wiring of my solar power system.

BJO8

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Hello, I just joined this forum. I don't have much understanding of electricty wiring, and would like to settle my doubts.

I recently had a 3 KW grid-connected rooftop solar power system installed in my house. It has net-metering so the power generated during the day can be used directly in the house while the excess power is sent to the grid; at night, power is drawn only from the grid, which will be adjusted with the amount I've sent to the grid during the day.

I've attached a diagram of the wiring.

Without the solar connection, the wiring is like - the wires from the power company first enter the three fuses at the bottom, then move on to the power company meter, then to the RCCB, then to three large switches, and then to smaller switches for different sections of the house. The wire from the solar inverter at the top of the house connects to the solar meter installed beside the power company's main meter, and then joins the grid.

Diagram:
8wyL1sw.jpg

Now, from what I understand, the wire from the solar meter should be connected below the RCCB so that it can supply the entire house as well as feed excess power to the grid. Instead, it is connected to the third large switch after the RCCB, and that too, above it. Is this kind of wiring correct? Does this mean that the power from the solar meter is going to only one section of the house, or is it going to the entire house?

I experimented a bit, and switched off the RCCB. I was expecting one of two things to happen: one, that since the wire from the solar meter is connected to the house wiring, even though I've broken the connection to the grid, power will remain on in the entire house, being supplied by the solar connection, or two, power in most of the house will go off, but will remain on in those parts of the house served by the third main switch. Instead, what happened is that when I switched off the RCCB, the power went off in the entire house; also, the solar meter also switched off (like it does at night). The solar connection was not feeding any power to the house at all at this time, and maybe it was not sending any power to the grid as well.

What I'd like to know is:

1: Has the wiring been done correctly, so that during the day the house is running on solar power (unless more power is needed and is taken from the grid)?

2: Is the entire house being served by the solar connection or only a part of it?

3: Was the behaviour displayed on switching off the RCCB correct?

4: Why did the solar meter turn off when the RCCB was switched off?

I'd like it if someone explains this in simple terms.

Thanks a lot.
 
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Kornbread

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Sorry, no answers to your questions, but seen the pic and had to comment. What is all that stuff in there? Dirt? I've never seen a service panel like that. Just my opinion, but it looks dangerous.
 

BJO8

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It's a really old house; it's dirt, cement and stuff.

I've removed the pic as that might be causing people to not answer. The diagram itself is faithful to the pic. I wish someone would give an answer.
 

Supervstech

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Wiring appears correct...
Switchboard are all common to each other...
The solar input appears to feed a breaker that feeds into the switchboard and distribute to the house...
European wiring isn't my strong suit...

If you disconnect mains from a grid tied setup, the solar disconnects, and would not provide power...
 

Supervstech

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Well... you removed the photo of the switchboard, and your drawing doesn't include all the wiring, so answers will be limited
 

Supervstech

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Sorry, no answers to your questions, but seen the pic and had to comment. What is all that stuff in there? Dirt? I've never seen a service panel like that. Just my opinion, but it looks dangerous.
In non US areas, voltages are higher, and switchboard areas are very different from ours.
 

BJO8

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Thanks for the reply.

It appears you have 3 phase mains power, but only single phase solar input.

Earlier, the connection was three-phase. The people who installed the solar equipment installed a single phase one and I asked the power company and they said it will be okay; they installed a new single phase meter for this, removing their old one.

Well... you removed the photo of the switchboard, and your drawing doesn't include all the wiring, so answers will be limited

The pic seems to be discouraging people so I removed it; in any case, it wasn't a very clear one. I understand that the diagram may not be sufficient.


Wiring appears correct...
Switchboard are all common to each other...
The solar input appears to feed a breaker that feeds into the switchboard and distribute to the house...
European wiring isn't my strong suit...

If you disconnect mains from a grid tied setup, the solar disconnects, and would not provide power...

Since you say the wiring appears to be correct, maybe I should leave it at that.

I still find the wiring to be strange, based on my understanding. The way I understand it is as something like a water line with three valves in it - you shut off the first valve and the water stops there, you shut off the second one and the water stops at the second valve, and so on. In the same way, the input from the solar should be connected below the RCCB to provide the whole house, but it isn't, it is connected way up, and yet the thing works; maybe the power just flows up and down? And what about the current from the solar inverter - when disconnected from the grid, where is all the solar-generated electricity going?

Like I said, I'm a noob in these matters. Thanks again for your reply.
 
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Supervstech

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Earlier, the connection was three-phase. The people who installed the solar equipment installed a single phase one and I asked the power company and they said it will be okay; they installed a new meter for this, removing their old one.

As for the pic, it seems to be discouraging people so I removed it; in any case, it wasn't a very clear one. I understand that the diagram may not be sufficient. Isn't it possible to answer the questions regarding the RCCB based on how you all install your systems? Like, does switching off the RCCB in your system exhibit the same behaviour as in mine?

Thanks for the reply.
The pic, got a single question concerned about the dirt...
You shouldn't consider that "discouraging people"
 

Kornbread

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Apologies if I discouraged you. I've never seen a service like that before and the dirt made me think it might have been under water. Keep at it, you'll get it sorted.
 

BJO8

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Apologies if I discouraged you. I've never seen a service like that before and the dirt made me think it might have been under water. Keep at it, you'll get it sorted.
Hey, no need to apologize. I myself am embarrassed posting a pic like that. :)
 
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