SAFE-T-CUT TRIPPING DAILY

[Metropolitian]

A roughly measurement by eyes:

We know that the main breaker would be approximately 35mm and in the picture below the cable covers pretty well 25% of that.

About 8mm and if you take the insulation and tape from that it would be at least 6mm. Then with the formula d = 2 × r

the bare wire would be theoretically at least 28mm².

 

Compare it with the wires on the bus bar, neutral link seems to be an 6mm, then 4 mm and 2.5 mm

_{(OR 4mm if the 2nd screw is a 2.5mm and the rest are 1.5/1mm but I think not as the 2nd wire looks stranded and 3rd and so on solid)}

 

[livram]

18 minutes ago, Metropolitian said:

 

On top of that, the blurry picture shows the cables from the utility lines to the meter. 

The consumer cable is on the right side of the meter.

OK, I double checked and confirm the numbers on the blurry picture are "600 Bolt" "2X6" and "064/2558" I mentioned that the meters on this road were recently moved to new longer poles and the blurry picture does indicate "newer cable". But the cable on the other side of the meter has no numbers or writing at all, very old looking.

[Metropolitian]

1 minute ago, livram said:

OK, I double checked and confirm the numbers on the blurry picture are "600 Bolt" "2X6" and "064/2558" I mentioned that the meters on this road were recently moved to new longer poles and the blurry picture does indicate "newer cable". But the cable on the other side of the meter has no numbers or writing at all, very old looking.

That confirms it that the newer cable, which is the cable connected to the overhanging wires, was replaced to reach the new height of the pole.

The old looking cable is the one that runs to your home and CU.

 

[livram]

It seems the consensus is that the main breaker is faulty. Do I just replace the entire 50 Amp STC CU Or do I replace the main breaker and RCBO unit (RMD 9)from STC for 1800 Baht. 

https://www.safe-t-cut.com/product/rmd-9-png/

It looks like my STC CU has a small screw under the 3-bar breaker and a small screw under the RCBO unit, can they be replaced and solve the problem.

[lopburi3]

13 minutes ago, livram said:

It seems the consensus is that the main breaker is faulty. Do I just replace the entire 50 Amp STC CU Or do I replace the main breaker and RCBO unit (RMD 9)from STC for 1800 Baht. 

https://www.safe-t-cut.com/product/rmd-9-png/

It looks like my STC CU has a small screw under the 3-bar breaker and a small screw under the RCBO unit, can they be replaced and solve the problem.

Yes if it indeed is the breaker - but do not do yourself as this will be a live wire that has to be removed and attached again (with no protection unless they disconnect at meter).  Whole panel believe 2 or 3 times the cost so no need to do that unless you have need for a number of new breakers (appears it still usable at a normal amperage level so could be used as a secondary panel without change).

[livram]

2 minutes ago, lopburi3 said:

Yes if it indeed is the breaker - but do not do yourself as this will be a live wire that has to be removed and attached again (with no protection unless they disconnect at meter).  Whole panel believe 2 or 3 times the cost so no need to do that unless you have need for a number of new breakers (appears it still usable at a normal amperage level so could be used as a secondary panel without change).

I will get a sparky from PEA if possible but I am just trying to see what options I have.

1. Will the RMD 9 1800 Baht just go into and replace the ones in the original CU?

2, I live 15 KM outside Korat in Khamthaleso. Where is the best place to buy SFC RMD 9 or better to buy direct from STC online?

 

BTW, it seems breaker is tripping more often now, sometimes will trip with 2 A/C on and/or trip with 3 A/C only.

[Metropolitian]

16 minutes ago, livram said:

I will get a sparky from PEA if possible but I am just trying to see what options I have.

1. Will the RMD 9 1800 Baht just go into and replace the ones in the original CU?

2, I live 15 KM outside Korat in Khamthaleso. Where is the best place to buy SFC RMD 9 or better to buy direct from STC online?

 

BTW, it seems breaker is tripping more often now, sometimes will trip with 2 A/C on and/or trip with 3 A/C only.

I am doing some research for sources and additional information for you right now..

 

A quick one: the product on the website of safe-t-cut is priced with the catalogus price directly from them, it is cheaper to buy them from retailers (of which buy in in higher quantities and thus cheaper and the price tag from them mostly is so)

[livram]

5 minutes ago, Metropolitian said:

I am doing some research for sources and additional information for you right now..

 

A quick one: the product on the website of safe-t-cut is priced with the catalogus price directly from them, it is cheaper to buy them from retailers (of which buy in in higher quantities and thus cheaper and the price tag from them mostly is so)

Thanks for the help. My thinking is that at this point when I hear about replacing cable from meter to house or going up in the ceiling and replacing cables and checking connections it seems the best option is to spend the 1800 baht and replace the main breaker and the RCBO and hope it fixs the problem. If not, will go on to the replacing cables, etc part.

[Metropolitian]

Livram, that would be the easiest way to go now.

Focus on the mainbreaker, which clearly seems the main issue playing now.

Tripping on a amp that is much lower then the rating of the main breaker.

 

In your case it is a Safe-T-Cut unit, and in this consumer unit the main breaker and the RCBO part are together one coherent unit. A failure in either the mainbreaker or the rcbo part means the replacement of this whole part.

 

In the STC units these modules dominate the biggest port of the price tag. In other styles consumer unit where these two are not fused together the replacement in case of module failure the cost lower.

 

Now I have found some B2C sources online and have a few results for you and I personally have good experience buying products that way. It is no different then buying from the original brands website, which mostly are higher priced and they are more B2B orientated.

 

The replacement module MAIN+RCBO Safe-T-Cut 63a (The RMD-9) is available from PJRElectric and cost 1420 THB.  CLICK

 

An option to consider, but not needed at all, is to buy a complete CU and use the needed module from that and keep the rest as spare (the breakers).

 

The same retailer sells the same module complete in a CU with 6 breakers (colored) for 2145thb CLICK

 

Another retailer (sakuragisk) ,has an 8 breaker version (also colored) but with 50amp mainbreaker/rcbo module which sells for 2230 THB CLICK

 

There of course are more out there but those one are actual and I do have experience with buying products from PJRElectric.

Not only they are an reliable -online- source with a real company, they offer fine products with a good price tag and communication and logistics were good.

 

I have bought from many other sources, mostly other branded products and on searching with the Safe-T-Cut, they showed up in the list. Hence my recommendation.

 

_{I will write some additional (non STC orientated) information in the next post.}

 

[Metropolitian]

1 hour ago, livram said:

I will get a sparky from PEA if possible but I am just trying to see what options I have.

1. Will the RMD 9 1800 Baht just go into and replace the ones in the original CU?

Yes such module will come in place of the faulty one.

 

1 hour ago, livram said:

2, I live 15 KM outside Korat in Khamthaleso. Where is the best place to buy SFC RMD 9 or better to buy direct from STC online?

Post #159 offers a few other online solutions. At this time _{(for future readers; Covid19-era)} online is the best solution. You can ask the sparky from PEA, or a local spark if it is a good one, to fix the module for a small fee in his pocket.

 

1 hour ago, livram said:

BTW, it seems breaker is tripping more often now, sometimes will trip with 2 A/C on and/or trip with 3 A/C only.

It is deteriorating..

[livram]

35 minutes ago, Metropolitian said:

Now I have found some B2C sources online and have a few results for you and I personally have good experience buying products that way. It is no different then buying from the original brands website, which mostly are higher priced and they are more B2B orientated.

 

The replacement module MAIN+RCBO Safe-T-Cut 63a (The RMD-9) is available from PJRElectric and cost 1420 THB.  CLICK

I am going to order from here today, I just wanted to sure that this will replace the ones I have in my STC 50 Amp CU. The lettering  and symbols are somewhat different. Will someone just be able to take out the original one and replace with the new one? Will it fit correctly?

 

Thanks again for your help and finding out where to order. Not many shops open around Khamthaleso.

 

[Metropolitian]

23 minutes ago, Metropolitian said:

I will write some additional (non STC orientated) information in the next post.

 

The following information is just my own personal opinion and experience.

In the post above (#159) I was mainly referring to the Safe-T-Cut units and the modules, which on itself are fine of the art products but they are very narrowed to their own line as it is hardly exchangeable with other brands.

 

Mind you, I am speaking about the products in the 35mm din rail 'world' , the click-on-systems are a world at their own of which are mostly Schneider/SquareD with a few other.

 

As the STC rcbo part has a different height compared with other brands, they only fit in their own line of boxes, and there that my opinion to myself to avoid these lines.

The un-interchangeable AND the coupled mechanism.

 

Two things; Firstly nothing bad with these brands they offer reliable service and safety and secondly even then the coupling can be undone with some modification, not advisable for rookies, like in the case with the RMD9 the mainbreaker can be unscrewed and replaced. Or this module mounted in another CU with some diy-ing modification of that CU.

They are perfect for use of smaller residents and with the residents never look to it again, for any upgrades or modification except in the events of failure as the OP is experiencing now.

 

For the advanced 'power-users'. It is better for the freedom of choice of modules and expandable and the replacement at a better cost to choose for other brands which offers modules (breakers,surge arresters, timers, etc.) each at their own.

 

I personally have a wide range of brands in use here, but the main CU is an 'Nano Classic' line, which are filled with mainly the Nano branded breakers, which I find useful as the breaker buttons are colored. In these units I do have a KwH (no-brand) for measuring the returned power from the solar installation and a few surge arressters and it is arranged in 3 groups and two of them are rcbo protected.

 

It is not only Nano that I am using here, no, I am using Holec/Eaton , Hager, Schneider, CT, ABB. A whole range which sits in other sub-consumerunits or powerracks.

 

Nano has two lines, The classic (freely modificable) and the new (sturdy?) Shihlin line which also has split units. Even the combined main/rcbo breaker, at which the sensitivity can be modified. (just like the Safe-T-Cuts RMD9).

 

Everyone is free to follow their taste. I just said mine.

 

 

 

[livram]

6 minutes ago, Metropolitian said:

As the STC rcbo part has a different height compared with other brands, they only fit in their own line of boxes, and there that my opinion to myself to avoid these lines.

The un-interchangeable AND the coupled mechanism.

The less modifications I have to make the happier I will be. I do not speak much Thai so I just say safety first and go from there.

 

So I take it that the main breaker/rcbo part will fit my CU. Correct?? I order a lot from Lazada but will now try to sigh up for Shopee. Last time I got frustrated so will try again.

 

When I receive the part and have it installed I will advise of the result. At least it cannot be any worse.

[Metropolitian]

12 minutes ago, livram said:

So I take it that the main breaker/rcbo part will fit my CU. Correct?

Yes.

[sometimewoodworker]

3 hours ago, livram said:

It seems the consensus is that the main breaker is faulty. Do I just replace the entire 50 Amp STC CU Or do I replace the main breaker and RCBO unit (RMD 9)from STC for 1800 Baht. 

https://www.safe-t-cut.com/product/rmd-9-png/

It looks like my STC CU has a small screw under the 3-bar breaker and a small screw under the RCBO unit, can they be replaced and solve the problem.

You do not have a 50A unit from your picture it is 63A

 

the unit you show is an equivalent one I don’t know if it is the correct size.

2 hours ago, Metropolitian said:

The replacement module MAIN+RCBO Safe-T-Cut 63a (The RMD-9) is available from PJRElectric and cost 1420 THB.  CLICK

That links to a 32A unit

 

2 hours ago, livram said:

Thanks for the help. My thinking is that at this point when I hear about replacing cable from meter to house

Nobody has yet suggested replacing the cables from the meter to the house.
 

So far you have not confirmed the size of that cable or posted a clear picture where the size can be seen. If they are too small you can add another set to bring them up to size.
 

the RCBO unit is clearly faulty. It would be a really really good idea to check the size of the cable feeding from the meter.

[livram]

10 minutes ago, sometimewoodworker said:

You do not have a 50A unit from your picture it is 63A

 

the unit you show is an equivalent one I don’t know if it is the correct size.

That links to a 32A unit

 

Nobody has yet suggested replacing the cables from the meter to the house.
 

So far you have not confirmed the size of that cable or posted a clear picture where the size can be seen. If they are too small you can add another set to bring them up to size.
 

the RCBO unit is clearly faulty. It would be a really really good idea to check the size of the cable feeding from the meter.

63 Amp Unit is correct, I started out getting a picture from HomePro STC 10 slot unit which is listed as 50 Amp but mine is clearly 63 Amp, I don't know where it was purchased.

 

The link is for 32A 50A or 63A, you click the picture and the correct price 1420 baht will show, I already ordered the 63A module so I hope that is going to fit.

 

Earlier it was suggested that perhaps the cables from the meter to the house were too small. The cable from the meter is very old and there are no numbers or writing so picture is no good. When sparky replaces module I will ask him the size of the incoming cable.

 

So when part received and replaced I will advise.

[sometimewoodworker]

1 hour ago, livram said:

Earlier it was suggested that perhaps the cables from the meter to the house were too small. The cable from the meter is very old and there are no numbers or writing so picture is no good. When sparky replaces module I will ask him the size of the incoming cable.

The cable size guess came from the numbers you posted, which may be/probably are incomplete) as it was incorrectly assumed they were feeding the house.
 

I don’t have any cable bits that I can lay my hands on to take pictures for you to easily judge the size of supply.

It’s difficult if not impossible to tell the size if you can’t see the cores as you could have big cores with thinner insulation or smaller cores with double insulation.

 

The pictures are not clear enough to be sure, though they do look as if they not 6mm. The cable going to the neutral bar is the one that suggests that they are 10mm or 16mm

 

Anyway if fortune smiles your new RCBO will fit and your problems will be over

 

it could be entertaining to open up the faulty unit to see if there is anything obvious that has caused the problem, like ants. On that note I am now always adding ant powder to any box or light fitting I open, in the hope that it will prevent later problems, it may work and is cheap insurance.

[Metropolitian]

1 hour ago, sometimewoodworker said:

3 hours ago, Metropolitian said:

The replacement module MAIN+RCBO Safe-T-Cut 63a (The RMD-9) is available from PJRElectric and cost 1420 THB.  CLICK

That links to a 32A unit

Yes and no. The link is correct.

That links to the product RMD-9 and there you can choose from three models (in amps), the 63amp is one of them.

 

 

 

For the sparkies here.

 

1 minute ago, sometimewoodworker said:

The pictures are not clear enough to be sure though they do look as if they not 6mm. The cable going to the neutral bar is the one that suggests that they are 10mm or 16mm

About right , like as I 'measured' in post #151 .

We are happily to know your opinion and other, still it's speculation

Because..

3 minutes ago, sometimewoodworker said:

incorrectly assumed they were feeding the house.

Was about the feed from the utility wires to the meter, but also apply with the wires from the meter to the house.

We don't know if the incoming wires in the CU are the one same wires that are coming from the meter itself until truly confirmed after inspection where the wires joins the roof cavity.

 

In my case From the utility wires to my consumer unit there was 3 wires sequentially from the Utility Wires -> Meter -> Home Rooftop -> Consumer unit.

 

[livram]

My breaker/rcbo RMD9 unit just arrived. Now my PEA guy has suddenly become unavailable so I have to find someone else.

 

I thought about trying to install on my own but this new unit is a little bit different. The breaker side looks the same but the RCBO side is a little over an inch narrower but same height on the new unit. It looks like a matter of connecting 4 wires line (l+n) and load (l+n). After connecting the wires it looks like the unit snaps into place.

 

In the USA it is easy to disconnect the power at the meter by flipping the lever but I do not see how to disconnect the Thai meter.

 

Will advise outcome when new unit installed.

[bankruatsteve]

4 minutes ago, livram said:

I thought about trying to install on my own but this new unit is a little bit different. The breaker side looks the same but the RCBO side is a little over an inch narrower but same height on the new unit. It looks like a matter of connecting 4 wires line (l+n) and load (l+n). After connecting the wires it looks like the unit snaps into place.

 

In the USA it is easy to disconnect the power at the meter by flipping the lever but I do not see how to disconnect the Thai meter.

I have never been inside a Safe-T-Cut CU, but most main breakers will have only the mains (L+N) connected.  The "load" is from the disparate MCB's which are usually on a bus connection to the main breaker.  The only way I have heard to isolate the mains at the meter is to disconnect at the meter which requires breaking a seal so it seems the PEA should get involved but the local sparks just do it.

[sometimewoodworker]

23 minutes ago, bankruatsteve said:

I have never been inside a Safe-T-Cut CU, but most main breakers will have only the mains (L+N) connected.  The "load" is from the disparate MCB's which are usually on a bus connection to the main breaker.  The only way I have heard to isolate the mains at the meter is to disconnect at the meter which requires breaking a seal so it seems the PEA should get involved but the local sparks just do it.

Don’t forget it is an RCBO 

[bankruatsteve]

2 minutes ago, sometimewoodworker said:

Don’t forget it is an RCBO 

Oh, right.  Where does the L out go?  (I've never had an RCBO for the main breaker either.  ????)

[sometimewoodworker]

Just now, bankruatsteve said:

Oh, right.  Where does the L out go?  (I've never had an RCBO for the main breaker either.  ????)

I would assume to the line bar feeding all the other breakers

[Crossy]

Any local sparks "should" be able to do the swap, the connections ought to be the same. Take photos before starting work.

 

Don't let him try it live, pull the live at the meter (don't pull both, he WILL get them the wrong way round when re-connecting).

 

 

[livram]

3 minutes ago, Crossy said:

Any local sparks "should" be able to do the swap, the connections ought to be the same. Take photos before starting work.

 

Don't let him try it live, pull the live at the meter (don't pull both, he WILL get them the wrong way round when re-connecting).

 

 

Good idea about the photos. Here is a picture of the unit to be installed.

https://shopee.co.th/product/105995009/2290968773

 

Crossy, the breaker/rcbo unit I have now is about an inch  wider than the new unit and it looks like it "snaps" in. The breaker side looks to be about the same size and the rcbo side is about an inch narrower.

 

Do you think this will be a problem?

[Crossy]

Yeah, they clip on to the DIN rail. Your man ought to know how to get the old one off and clip on the new one.

 

Once it's all done you'll have a hole which you should cover. You can get clip-in blanks but in the absence of those a convenient sized piece of plastic siliconed to the inside of the cover should do the trick.

 

[albertik]

I am not in any way trying to be a smart ass. Smart no, ass maybe. I was having a very similar problem. Not being smart when it comes to electric in my home, I finally just asked my local sparky to replace the safety cut, and even though the old one had been serviceable for 8 years, he replaced it and problem was solved.

At any rate...…. chok dee

 

[lopburi3]

25 minutes ago, albertik said:

I am not in any way trying to be a smart ass. Smart no, ass maybe. I was having a very similar problem. Not being smart when it comes to electric in my home, I finally just asked my local sparky to replace the safety cut, and even though the old one had been serviceable for 8 years, he replaced it and problem was solved.

At any rate...…. chok dee

 

This is what they are doing - in this case it is a power panel and Safe-t-cut is apart of it rather than the often seen Safe-t-cut RCBO installed independently.  I still have original model from about 1978 and still working fine.  

[Metropolitian]

2 hours ago, livram said:

The breaker side looks the same but the RCBO side is a little over an inch narrower but same height on the new unit

Yes, your old module is a RMD3 from the Gold series of STC. The official distributor of SafeTCut stopped selling these as they have now the new model RMD9 in stock.

There are still retailers that have the RMD3 in stock , old stock.

 

The RMD9 has the room (with text 'disconnect L N ,dieelectric test' ) between the RCBO and Mainbreaker removed, so the module is a bit smaller.

 

Tip: in the future you can have a surge protector at the left side of your consumer unit to protect your equipments from HV spikes or have an extra breaker at the right. Meanwhile this gap can be closed with a piece of plastic.

 

RMD 3                and the                    RMD 9

[Crossy]

1 minute ago, Metropolitian said:

Tip: in the future you can have a surge protector at the left side of your consumer unit to protect your equipments from HV spikes or have an extra breaker at the right. Meanwhile this gap can be closed with a piece of plastic.

 

Very smart idea ????