View Full Version : Current in Ground wire in wall sockets
irus
Apr 23, 2009, 11:46 AM
I live in delhi india and around 2 years back moved into an apartment where I got the rewiring done.
It seemed OK until the aircon switch in the voltage stabiliser kept burning up and had a foul odour. So I read up on it and checked polarities and it was reversed. But in the wall socket polarities were fine. So I lined up the plug voltage stabilizer polarities and now the wire from wall to the aircon stabiliser is heating instead of the stabiliser socket+aircon plug burning. I've yet to open that wall socket.
However I checked all light and power sockets in the home with a three prong tester. In 12 of them it shows live/hot(its called phase wire in india) reversed with neutral and in 6-7 of them it shows Ground Opp. Not sure what it means but ground wire lights up the tiny bulb inside the screwdriver but has no current to light a bulb from it. The neutral in the socket too lights up the screwdriver.
There is no sophisiticated meters with me yet. And the electricians here don't really care or know about polarities even! So I'm keen to have this fixed. Anyideas where to start and what to do.
I'm attaching the pics
tkrussell
Apr 23, 2009, 04:03 PM
Wow, I sure am dizzy now.
Not sure if there is anyone here familiar with this material or system. I remember a new member signing in Introductions as an electrician from New Zealand, never saw him again.
Need to know make and model to see datasheet of what appears to be outlets and or switches fitting. Looking at the back not much help.
And the Consumer Unit/Breaker Panel. May be easier for you to find manufacturer websites and download datasheets, would be local to you.
Is this a Ring Main System?
What is the voltage and local color code of wiring system?
I believe it is 230 volt, one line grounded neutral, blue, and brown, hot, green equipment ground.
If your going to tackle this yourself will need a voltage tester/meter. Check local codes if you can do your own work, and what are safety practices are. Here in the US we need to dress like astronauts nowadays. But this stuff takes no prisoners, so safety first, esp for a DIY'er.
My guess is one or all of the following condition, an open neutral, illegal neutral/equipment ground connection, poor grounding of the grounding system, along with the reverse polarity you had/have.
irus
Apr 24, 2009, 02:34 AM
I doubt electricians here go into datasheets! The make of these MCB's is Havell on havell.com
Ring main system? I'm not sure what that means sorry?
The voltage is 240. From what I could make out on the left side is the busbar for light points and on right side busbar for heavier things like aircon
I think the color coding which uve figured is right.. the red and yellows are live. The black and blue neutral and green is earth.
I've figured this is outside my scope to handle! So called in an electrician with a multimeter! Lol
Can you tell me where should this investigation start? Also should the 10-12 sockets with reversed polarities be corrected first or should neutral be hunted for or grounding issues be tackled first?
What does illegalneutral/equipment mean? Apologies for so many questions! I'm new at this! And trying to figure out because I've lost a laptop and aircon because of this wiring! :(
irus
Apr 24, 2009, 02:46 AM
That's havells.com
tkrussell
Apr 24, 2009, 05:47 AM
Here is the brocheure for Havells distribution panels:
http://www.havells.com/Admin/Forms/Brochures/DP%20Catalogue.pdf
But I don't find one that looks exactly as yours, but I get the idea.
What I really need was datasheet for the wall device, first picture showing the back of a device, without seeing exactly what this is, I have no idea what all the red, yellow, and black wires are doing.
Both the reverse polarity and neutral grounidng issues needs to be resolved. Both are a priority.
The illegal connection I refer to is somewhere in the branch wiring, sockets, etc, there may be a accidential or improper connection between the green grounding conductor and the blue or black neutral.
This is a complex issue to troubleshoot, and knowledge and experience with this system is needed, so may be best to have a professional come in.
A Ring Main is a system used in UK and maybe Europe. Usually a 30 amp circuit is run thruout the home to each socket box and returns to the Consumer Unit. Can be considered as a distribution bus. And since it returns to the CU, it literally is a ring of conductors from start to finish.
Then at each socket box, the exact socket, with the approriate fuse protection and Residual Current Protection device is installed that is needed at that utilization point.
I do not think you have this system, as the CU seems to contain the RCD's.
Don't the electricians there use instructions of the equipment thaty are installing? That is what a datasheet would be helpful with.
irus
Apr 24, 2009, 09:30 AM
I went through the brochure it seems like they've introduced a new series of products for 2009.
Well coming back to the problem today the electrician came and I told him the story briefly he got at work first finding the ground. The ground wire between two sockets was missing!
As you can see in pic labelled 1 there are only reds and yellows live wires and one neutral. No earth wires!
In pic labelled 2 this plate is the one on the same wall behind the plate in photo 1. now these guys spotted the earth as present but disconnected somewhere 6 feet above this plate in the wall close to the ceiling
In pic no.3 u can see a yellow wire... that's the patch they installed to connect plate of photo 2.
In photo for you can see the earth wire in plate of photo 1. they again pulled this earth wire down from the box in the previos pic. This was used for the fridge earlier and it used to heat up a lot, we moved it from their luckily while doing some furniture shifting. And offlate it was being used for the microwave which sometimes wouldn't turn on! No wonder.
This fixed 2 ground problems very quickly. Surprisingly efficient work. Then the remaining 4 ground sockets were fixed ingeniously... at the outset it seemed impossible to have wires turning around walls and roofs as it was cut somewhere... but they managed to connect the bad earth with some other nearby sockets earth without any sweat.
After this they reversed all the 10-12 sockets which had reverse polarity. The total job took around 4-5 hours and they took no breaks.
Total cost: $13
Lot of relief now. The guy finally took out his multimeter and stuck one node into the live and one into neutral it showed 0.00 so no problem with earth anymore I suppose!
I guess case closed for now. Thanks tkrussell and others for reading!
tkrussell
Apr 24, 2009, 09:58 AM
Two men 4 to 5 hours each and the bill was $13.00.
Here that is the cost for lunch for one man.
I am glad you were able to get this repaired quickly there.
Doing it here would have taken some time, that I don't think you had.
Thanks for the feedback and follow-up.
KISS
Apr 24, 2009, 10:09 AM
My $.02:
I've seen systme slike this for equipment, but not houses.
I don't know what some of those devices are.
What I specifically don't like about that entire setup is what looks like a daisy chained hot with two small of a wire gauge.
That system should be bussed correctly.
There is a DIN terminal with a center bar (usually 10 connections) which can be connected to a larger wire size.
The breakers would be run to this bus.
Yet another multi-lug (Not DIN can be used to distribute the main power.
The system is used extensively when distributing power to a piece of equipment.
We took a cheap way out when we needed about 7 circuits at 120 V, 10 A. Just mounted a load center on the side of the equipment rack and plugged it into a 60 A plug.
The odd part is that the equipment could be 120 V or 100-240 or 208. The 208 had long lead times. So there was a mix. Some took up a small er footprint. Preference is now the 100-240 slim version.
Stratmando
Sep 5, 2009, 10:12 AM
Quote "the guy finally took out his multimeter and stuck one node into the live and one into neutral it showed 0.00 so no problem with earth anymore i suppose!"
Here, we have a Hot(phase), and the Neutral and Ground. Neutral and Ground are both at Same potential, connected together at the Service, From there, the Neutrals connect to a Neutral Buss and the Neutrals carries the load of the circuit. The Ground Does NOT carry current unless a short or leakage occurs.
When testing, we look for voltage between the Hot and neutral, and between hot and ground, You DO Not Want to find voltage between Ground and Neutral.
I go with kiss on the Series and wire size "Apearing" a little strange.
Seems like 1 person could check out and correct 10-12 plates in an Hour?
On photo 2, is that picture on the back of the plate some type of approval?