Domestic Instal in Thailand - Phase 2 - Testing

[Thai Amateur]

At last I've been able to complete theelectrical installation of the bungalow. Taken so long because I'vehad to fix so many problems with the building work left by my earlierlocals.
So now I've done some preliminarytesting and YES I am going to get a local professional in to do thefinal testing but I want to make sure that I haven't made any majorerrors. Plus I want to make sure that any local I get really doesknow how to test properly.
I have a Kyoritsu model 6010A multitester.
1. Tested continuity – OK.
2. Tested conductor resistance R1 + R2.Compared result with recommended length of cable for voltage dropmultiplied by the resistance for the cable size. Problem with spurs Iadded to water pump and car port but overcame this with anothercircuit. All R1 + R2 well within the recommended parameter.
3. Test Insulation (at 500v).
Here I seem to have a problem althoughI can't see why. I have 2 consumer units supplied from a single main(3 pole) disconnecter switch.
First I connected L-N and tested L-E.
Unit 1 – 160 Mohms
Unit 2 – 80 Mohms
Next I removed the link and tested L-N,L-E, N-E.
Unit 1
L-N - 0.11 MOhms
L-E – 140 MOhms
N-E – 195 Mohms
Unit 2
L-N - 0.08 MOhms
L-E – 60 MOhms
N-E – 70 Mohms


First time I've done anything like thisso any advice would be most appreciated.

 

[Thai Amateur]

Sockets etc. werethe best I could find that matched up. Could have had mix betweensockets and switches which were more expensive but didn't look anybetter anyway.
Couldn't get 6mmcable for the cooker with included earth so had to go for separatecables.
Water supply isplastic but the kitchen sink will be metal. Should this be bonded?


Regarding the earth.I first sank 2 rods down to over 3.5 metres with a separation over 4metres. Then I got to thinking about what you said about waterlevels. I have 2 septic tanks (Thai style) so I sank an additionalrod into the outflow from each and connected them all up with 16mmcable.
The whole system isnow about 14 metres end to end with each end being in a septic tankfield. The ends should be permanently wet but I'll have to wait andsee if the centre rods are within the actual water level.



Is there any way Ican measure the earth without connecting the main supply?

 

[Engineer54]

Sockets etc. were the best I could find that matched up. Could have had mix between sockets and switches which were more expensive but didn't look any better anyway.
Couldn't get 6mm cable for the cooker with included earth so had to go for separate cables.
Water supply is plastic but the kitchen sink will be metal. Should this be bonded?

No, the bonding requirement is for metal work/pipes etc, that will be bringing extraneous earths into the property

Regarding the earth.I first sank 2 rods down to over 3.5 metres with a separation over 4 metres. Then I got to thinking about what you said about water levels. I have 2 septic tanks (Thai style) so I sank an additional rod into the outflow from each and connected them all up with 16mm cable.
The whole system is now about 14 metres end to end with each end being in a septic tank field. The ends should be permanently wet but I'll have to wait and see if the centre rods are within the actual water level.



Is there any way I can measure the earth without connecting the main supply?

Only by using a dedicated 3 stake earth tester i'm afraid. So just wait until you can test with your MFT meter.
Sounds like you could well be achieving some very decent Ra values for those rods.

As i remember you have two houses (bungalows) next door to each other, one you and your family live in and the other is for rental. Haha, earthing wise you may well have the safest two houses in the village, if not in the State!! lol!!

 

[Thai Amateur]

As i remember you have two houses (bungalows) next door to each other, one you and your family live in and the other is for rental. Haha, earthing wise you may well have the safest two houses in the village, if not in the State!! lol!!

Unfortunately my own house was "electrocuted" by my father-in-law. Electrician ??? Worked on the local US air base during the Vietnam war an hen spent 14 years working in Saudi.

When I've finished the bungalow I am going to have to spend a serious amount of time trying to sort out the "errors" (can't use what I really mean - :drunk:.
Example: the only external connection to earth I can see is a single wire buried in the pathway abut 2 cms from the house wall. This might be the supposed earth but I suspect it is from the lightning conductor he insisted should be installed.

Changed the oven and Hob just before Christmas and found that he'd wired the cooker circuit directly to the main 63Amp circuit breaker.

Had to check the earth for the water pump. Wiring is in the toolshed. Found ALL the wires were black - Live, Neutral & Earth.
So That's why I really want to get the bungalow right.
Sorting out my house will be an absolute nightmare but at lest I think I'm beginning to understand hat is needed.