Upgrading Electrical Distribution

[pe747]

Our house was built in mid 2016. The circuit breaker board looks like the foto below.

 

 

Until now I have had only problems with LED and standard light bulbs that were blown. Fortunatly no expensive electrical devices such as TVs, refrigerators, airconditioners or computers broke so far. But I am a bit unsure if it would be good to install under/overvoltage protectors or other equipment to be safe. 

If somebody could give me directions, it would be highly appreciated. Also for and address of a qualified electrician in Cha Am/Hua Hin area.

[bankruatsteve]

Light bulbs can blow for reasons unknown but probably related to quality of vendor.  If you have jinky service, you might be best served with an AVR/AVS that fits your demand.  i have two AVS from Global that I have been happy with.

[Crossy]

I see no earth leakage protection, so task A would be to install either a front-end RCBO or individual RCBOs on "risky" circuits (water heaters, outdoor outlets and lighting, wet room outlets etc.).

 

I do note that you have a 100A incoming breaker so I'm assuming you have a 30/100 meter, unfortunately I don't think you can get a 100A RCBO that will directly fit in place of it ???? 

 

Schneider do plug-in surge arrestors that should fit that board, you'll need to shuffle the MCBs a bit to fit one but nothing major. That will sort any lightning issues should they occur (you don't seem to have had such issues, yet, but it never hurts).

 

Actual under-over voltage protection is more complex with the plug-in boards, so unless you actually have chronic voltage issues I wouldn't bother.

 

[pe747]

Thanks Crossy for your reply.

Would this https://www.lazada.co.th/products/dz47le-1p-n-100a-d-230v400v-50hz60hz-rcbo-i2963943492-s10877333663.html?spm=a2o4m.searchlist.list.111.3bd74a16fTHdVj&search=1

suit the frontend rcbo 100A?

And what about something like this https://www.lazada.co.th/products/svp-977l-230v-digital-lcd-curren-overvoltageundervoltage-backlight-i2691349395-s9704068097.html?spm=a2o4m.searchlist.list.37.17908d15Nh5cAB&search=1

 

Regards

Peter

[Crossy]

@pe747  your problem is that you have a "plug-in" type distribution board, the units you link to are DIN mount, sadly they fitteth not ???? 

 

 

[pe747]

Ok, but then I could replace the distribution board and all the breakers to a din type and use the two linked units. Could I?

[Crossy]

12 hours ago, pe747 said:

Ok, but then I could replace the distribution board and all the breakers to a din type and use the two linked units. Could I?

 

Yes of course, and using a DIN system opens up the possibility of using lower-cost surge supression too.

 

Choose your new distribution board wisely to take account of any future updates such as adding solar or a standby generator. Crossy Mission Control has, shall we say, "evolved" over the years and is a bit of a mish-mash. if I was doing it again from scratch I'd do it rather differently.

 

[pe747]

Thank you for your suggestions and kind help. Appreciate.

Peter

[KannikaP]

Why not get another 'box' with DIN fitting surge protection, RCBO etc. Put that above the 'old' one and feed to the existing one.

[Crossy]

31 minutes ago, KannikaP said:

Why not get another 'box' with DIN fitting surge protection, RCBO etc. Put that above the 'old' one and feed to the existing one.

 

Yeah, it looks like he has plenty of slack in the incoming supply to add another box with the new gubbins in ???? 

[pe747]

Sounds like a great idea????

[pe747]

Checked powermeter near the street, its new, recently added and rated 30/100. Funny though, the main breaker in the CU, as Crossy mentioned, is a 100A breaker but the breaker before the Line and Neutral comes into the house is a 63A breaker.

Questions for the additional box:

RCBO: would I need a 1P+N 100A type?

For a frontend over/under volt SPD, I found maximum 80A device. (Sinotimer SVP-977L) would that work?

TKS

Peter 

[Crossy]

OK, firstly I'd check that the 63A breaker really is breaking the supply to the house, it does seem odd that someone would go 100A meter and incomer then slug it with a 63A in the middle.

 

For your new box:-

• Since you are retaining the existing over-current protection you just need an RCD rather than an RCBO (should be slightly cheaper), on the incoming supply it should be 100A 2P.
• For your over/under, I wouldn't trust the "80A" unit at over 40A (I've seen inside them), better to use a separate sensor unit and external contactor.
• Note that you will still need a surge supressor (the under/over is way too slow).

 

[pe747]

2 hours ago, Crossy said:

OK, firstly I'd check that the 63A breaker really is breaking the supply to the house, it does seem odd that someone would go 100A meter and incomer then slug it with a 63A in the middle.

I guess that when building the house there was a lower rated meter at the pole on the street. So the electrician (sparky as you call them) installed a 63A breaker before the house (Street to house 150m)

This new 30/100 meter was just installed during summer, when we were in Europe.

2 hours ago, Crossy said:

 

 

For your new box:-

• Since you are retaining the existing over-current protection you just need an RCD rather than an RCBO (should be slightly cheaper), on the incoming supply it should be 100A 2P.

 

Do you mean by existing over-current protection the main breaker 100A in my CU?

 

Could you give me a suggestion how my new box on top of the old one should be equipped?

 

Sorry for the dumb questions. I am no better than a sparky here????

[pe747]

BTW,

what is the correct type for RCD. AC, A, B?

[Crossy]

14 minutes ago, pe747 said:

BTW,

what is the correct type for RCD. AC, A, B?

 

To be honest, here, whatever you can get.

 

Unless you have a lot of electronics any one will do the trick (Type A is good to 6mA of DC).

 

If you have an EV charger then Type B is your beast unless the charger has a built-in Type DD (check the installation instructions).

 

https://hager.com/uk/get-involved/news-and-press/ev-charging-and-rcds

 

Important Note - this "Type" is not the same as the "curve" of an MCB, plenty of space for confusion.

 

[pe747]

I decided to install a new consumer unit.

Here is my new baby:

 

 

Need another terminal block N for the split setup 

I am just waiting now, that all the breakers and gadgets come. Hope to do the switch over by mid January. When I have all the stuff, I'll post a picture of my intended setup to ask your advice if that is reasonable.

In the meantime, if you could kindly answer me following questions:

1) To install 2 RCCB, SPD, Wattmeter I'm gonna need wire. In my current CU I see most  

    wire is 4 sq.mm. Is that ok if I go from the main breaker (100a) to SPD etc with that 

   size wire?

2) My plan is to switch off incoming breaker before the house when doing the job,       

    measuring if there is still current in the CU, if safe, connect all the "line" wire ,

    earth wire. Then carefully switch on one breaker after the other and see, which

   neutral belongs to which terminal block. Does this sound reasonable?

3) Should I get somebody to replace the 63a breaker before the house for a 100a?

 

Thanks again for commenting.

Peter

 

[pe747]

Good morning Crossy and other experts for CU

 

I have got all the breakers and gadgets now and made a photo of my intended setup. Still waiting for some cables to come.

Would you please take a look at my CU and make suggestions, if I miss something important?

Thank you 

 

 

[BritManToo]

On 12/31/2021 at 10:05 AM, pe747 said:

Then carefully switch on one breaker after the other and see, which

   neutral belongs to which terminal block. Does this sound reasonable?

Nope, can't see how that would work.

I'd use a shorted plug, plug it into the socket of the circuit you want to find.

Back to the fuse box, put one end of a Ohm meter on the live, then run the other end along the neutrals until you find the neutral with ZERO resistance. Remember to pull out the shorted plug.

Don't put the breakers on until every wire is connected. 

[pe747]

4 minutes ago, BritManToo said:

Nope, can't see how that would work.

I'd use a shorted plug, plug it into the socket of the circuit you want to find.

Put one end of a Ohm meter on the live, then run the other end along the neutrals until ZERO resistance. Remember to pull out the shorted plug.

Don't put the breakers on until every wire is connected. 

Thanks for this useful tip

[Crossy]

1 hour ago, pe747 said:

Would you please take a look at my CU and make suggestions, if I miss something important?

 

I would give at least your live side surge arrestor an MCB, say 20A just in case the internal disconnect fails to operate when the unit "expires".

[pe747]

6 hours ago, Crossy said:

 

I would give at least your live side surge arrestor an MCB, say 20A just in case the internal disconnect fails to operate when the unit "expires".

Do I understand this correct? I put a MCB before the SPD? Thanks for clarifying>

[Crossy]

37 minutes ago, pe747 said:

Do I understand this correct? I put a MCB before the SPD? Thanks for clarifying>

 

Yes, feed the SPD via an MCB.

[pe747]

17 hours ago, Crossy said:

 

Yes, feed the SPD via an MCB.

Thank you for your answer.

I have a spare 25a MCB single phase. Would that do it or should I buy a 2pole MCB for that purpose?

[Crossy]

The single pole 25A would do the job perfectly. You just need to protect the live side.

 

[pe747]

Thank you Crossy for your help.

You made my day????

[pe747]

Finally got all my cables and gadgets.

Today was the big day. Switched everything to the new CU box.

Everything working fine except two things:

Had all my kitchen things to one RCBO (yellow arrow)(fridge, stove, dishwasher, water pump etc)

But the RCBO doesn't allow to be switched on, just trips. So for a temporary solution, I put that circuit to a regular MCB, as it was before. Gonna order another one to see if the RCBO from China was faulty.

The second thing is: just recently I have a short in the outdoor lighting and if I switch the lights on (on Nr 1 MCB) the corresponding RCD trips. Gonna call the sparky, who installed all the lighting. He put all the connection boxes underground and probably water has immerged inside one of the boxes.

 

Wanna say thank you to all the people that contributed to this project.

Peter

[sometimewoodworker]

4 hours ago, pe747 said:

But the RCBO doesn't allow to be switched on, just trips. So for a temporary solution, I put that circuit to a regular MCB, as it was before. Gonna order another one to see if the RCBO from China was faulty.

It’s really unlikely that the RCBO is faulty. It looks as if you have at least 2 that are functioning so you may be able to do a quick test by swapping them, even if only for a few minutes, the power rating would be irrelevant for the test period since you wouldn’t be loading the circuit too much.

 

I would bet on it being a borrowed neutral and you are very probably going to have a lot of fun (not) finding it. We had on of those and it took an actual electrician a few hours to find it. Unfortunately the vast majority of people doing electrical work in Thailand aren’t electricians and don’t really understand the theory or have the testing equipment.

[pe747]

16 hours ago, sometimewoodworker said:

I would bet on it being a borrowed neutral and you are very probably going to have a lot of fun (not) finding it. 

Spent the day lookin for the problem. Had a nearby solar plant electrician come, but he did'nt find the problem too. So, after he was gone, I still wasted half the day for looking after the problem. I found out, that the cirquit nbr. 3 in my foto above tripped the second RCD in the morning too. On that cirquit is the garage and the submersible water pump. My wife was out in the garden early in the morning watering the plants and when the level switch started the pump, the RCD got tripped.

So, most probably the garage life and its neutral were correctly attached to the second RCD and the garage door operated without fault last evening. But when the pump started with probably Neutral borrowed from kitchen cirquit that tripped the RCD and probably RCBO last night. To troubleshoot, I'll disconnect all neutrals, exept kitchen cirquit neutral and see, if submersible pump still runs on an unprotected MCB.

An other thing is the second over/under voltage protection device in the lower row shows amps 0 all the time although consumers are connected and in use. What could there be my mistake?

 

 

[Crossy]

44 minutes ago, pe747 said:

What could there be my mistake?

 

Swap it with the other to verify it's not duff.

 

Verify there's nothing bypassing it on the live side.