Explain transformer or other options

[tattoodrob]

Thanks for all the help/answers.

So since i now have an RCD safe t cut then should that switch off if i have an open neutral again as i havent had problem since so not sure and only ever happened like that when had the  powercut/on but i didnt have rcd then,could water heater box  neutral/ground been the problem 2 times?....i could smell the burning of the metal hoses and water leaked!.......im supposed to have ground rod and everything ok but dont know how to check now but when installed everything then said he did it!!

i have not found a proper electrician ever since being here and even with problems with other  places ive owned in different towns.

Example:

I use to get electric shock using the  shower in a condo i owned..like a buzz shock from metal pipe/shower tap.......so thought was heater unit.......took to fix..no problems with it but still shock,ask sparkys to come ,had a couple  but couldnt sort the issue,one even ran my own ground from shower to the earth outside the condo long way still same..in the end had to change all external water pipes for shower to plastic so no metal and so sort of helped but metal pipe from wall would still buzz if touched.......was there a problem with someone elses electric that could have been touching my pipes as i think still got buzz when shower turned off ..nightmare,what you think it was??

[Crossy]

OK, in order to go further we need to know exactly what you have. Please post decent photos of the Safe-T-Cut and distribution board with the lids off.

 

Power off and TAKE CARE, there will be live wires inside even if the power is off. Make sure we can see the internal wiring clearly.

 

Have a hunt for a ground rod, unfortunately they are often buried or hidden under concrete.

 

As to the issue in your condo. I reckon that was caused by a difference in potential between "real" ground (the pipes and building steelwork) and the electrical ground (assuming TN-C-S). The two grounds should have been cross-bonded where the supply entered, but of course TiT.

[RichCor]

19 minutes ago, tattoodrob said:

I use to get electric shock using the  shower in a condo i owned..like a buzz shock from metal pipe/shower tap.......so thought was heater unit.......took to fix..no problems with it but still shock,ask sparkys to come ,had a couple  but couldnt sort the issue,one even ran my own ground from shower to the earth outside the condo long way still same..in the end had to change all external water pipes for shower to plastic so no metal and so sort of helped but metal pipe from wall would still buzz if touched.......was there a problem with someone elses electric that could have been touching my pipes as i think still got buzz when shower turned off ..nightmare,what you think it was??

 

Electricity wants to travel from the transformer to the transformer, normally over LIVE to NEUTRAL or Live Phase(1) to Live Phase(2, 3, etc) circuit connection, or over the Protective Conductor (Earth-Ground) sometimes but not always used with a companion Automatic Disconnection of Supply device.

 

If you were standing in the shower area and got a 'buzz' off the metal pipe work then you were completing a circuit connection. From 'what' to 'what' is the question. Usually both the tile floor -and- the metal pipe work are associated with earth-ground, but in your case one or both of them were closer associated the Live, Live Phase 2 or 3, unbonded or open Neutral, or ineffectual Earth-Ground protection. The 'power leak' could have been from your CU Circuit Breaker or even another tenant in the building. When you touched the pipe work you completed the circuit (or a shorter more efficient circuit) than one potentially already in place.  

 

The Protective Conductor (Earth-Ground) under normal conditions will carry very very small voltages or currents, and only larger currents during fault conditions.  If you added a dedicated earth-ground wire connection and still got a 'buzz' shock then a fault condition was in play and that wire to your supplemental earth ground rod must have been tens of meters away.

 

Since you didn't die instantly when you touched it I would assume the 'buzz' you felt was under 5ma and/or under 50 volts. Still, not something to leave be, since you don't know what's driving it or if/when it will get worse.  Using isolating plastic fittings might seem like a quick short-term solution, it really isn't a solution.

 

The first suspect is usually the shower heater. But as you stated, the technicians didn't find anything.

The second test would have been to eliminate the shower heater from the equation by physically disconnecting its wiring and checking if the stray current was still running from the metal pipe work to a functional earth-ground (with the aid of a Volt Meter, rather than your finger). If the stray current was still present after disconnecting ALL THE WIRES then something else is responsible for energizing the metal pipe work (or your tile floor).

[tattoodrob]

9 hours ago, Crossy said:

OK, in order to go further we need to know exactly what you have. Please post decent photos of the Safe-T-Cut and distribution board with the lids off.

 

Power off and TAKE CARE, there will be live wires inside even if the power is off. Make sure we can see the internal wiring clearly.

 

Have a hunt for a ground rod, unfortunately they are often buried or hidden under concrete.

 

As to the issue in your condo. I reckon that was caused by a difference in potential between "real" ground (the pipes and building steelwork) and the electrical ground (assuming TN-C-S). The two grounds should have been cross-bonded where the supply entered, but of course TiT.

Can't turn off power as night time but here attached some pics I hope,breakers have some c16,some c20 and some c30 so should I go ahead and buy the AVR or not yet as was going to call sparky I use to install soon.

or you still want see inside box more.Thanks.....by the way avr has voltage and an amp meter with switch to see input/ output.

[tattoodrob]

8 hours ago, RichCor said:

 

Electricity wants to travel from the transformer to the transformer, normally over LIVE to NEUTRAL or Live Phase(1) to Live Phase(2, 3, etc) circuit connection, or over the Protective Conductor (Earth-Ground) sometimes but not always used with a companion Automatic Disconnection of Supply device.

 

If you were standing in the shower area and got a 'buzz' off the metal pipe work then you were completing a circuit connection. From 'what' to 'what' is the question. Usually both the tile floor -and- the metal pipe work are associated with earth-ground, but in your case one or both of them were closer associated the Live, Live Phase 2 or 3, unbonded or open Neutral, or ineffectual Earth-Ground protection. The 'power leak' could have been from your CU Circuit Breaker or even another tenant in the building. When you touched the pipe work you completed the circuit (or a shorter more efficient circuit) than one potentially already in place.  

 

The Protective Conductor (Earth-Ground) under normal conditions will carry very very small voltages or currents, and only larger currents during fault conditions.  If you added a dedicated earth-ground wire connection and still got a 'buzz' shock then a fault condition was in play and that wire to your supplemental earth ground rod must have been tens of meters away.

 

Since you didn't die instantly when you touched it I would assume the 'buzz' you felt was under 5ma and/or under 50 volts. Still, not something to leave be, since you don't know what's driving it or if/when it will get worse.  Using isolating plastic fittings might seem like a quick short-term solution, it really isn't a solution.

 

The first suspect is usually the shower heater. But as you stated, the technicians didn't find anything.

The second test would have been to eliminate the shower heater from the equation by physically disconnecting its wiring and checking if the stray current was still running from the metal pipe work to a functional earth-ground (with the aid of a Volt Meter, rather than your finger). If the stray current was still present after disconnecting ALL THE WIRES then something else is responsible for energizing the metal pipe work (or your tile floor).

So not easy even for a qualified sparky to find and if is down to the building or from other room then near impossible to get fixed as no one was interested to help at the condo which was years old already,other country you would have chance if not from your room but here nearly impossible as no one cares and no one to complain to and get it fixed,I tried my best by getting multiple guys to come and check and even got new earth put in ,after that then that sparky was stumped and after reading what you said then i can understand why he couldn't do much more especially if not coming from inside my room as such.

[RichCor]

25 minutes ago, tattoodrob said:

 Appears this may be a 3-phase CU being used as a single-phase CU.  Which is neither here nor there, just interesting.

[RichCor]

17 hours ago, Crossy said:

On 5/10/2017 at 8:59 PM, tattoodrob said:

Fitting in line after rcd will be good and rcd still work but if fitting before then is no good as then rcd wont work properly right ?

The RCD will work just fine on the input or output of the AVR. But you must not connect the AVR directly to the incoming supply without some form of isolator. Fitting it after the RCD allows you to use the RCD as the isolator.

 

Question for @Crossy,

Installing an AVR, isn't it functioning as an isolating transformer creating questions on how an RCD, placed upstream or downstream, will function? And how to deal with where Neutral and Earth-Ground and how/where they are potentially bridged.

[tattoodrob]

19 minutes ago, RichCor said:

 Appears this may be a 3-phase CU being used as a single-phase CU.  Which is neither here nor there, just interesting.

Yes I think sparky didn't know I only could have 1 phase til after he bought the box for my house so utilized it

 

[Damrongsak]

I would check voltage drop at the meter/incoming line and at the point of delivery to the heavier appliances.  Putting in a step-up transformer is not a good cure for small house wiring.  Small gauge wires contribute to voltage drop and subsequent heating of the house wiring.  The more current you draw, the greater the voltage loss.

 

When I lived in Thailand, I had to heat water in the cold season in Loei.  I put a 5 gallon wash tub out in the sunny part of the yard and covered it with a bus window conveniently left by the former tenant.  By 4 pm the water and air were warm enough to "shower" with, using a dip ladle. I did have a small transformer, but that was so the single fluorescent light had enough voltage to light up in early evening.  The other couple of incandescent bulbs would work just dim.  I did have a fan and radio.  I recall one electric bill was about 5 Baht for the month.

 

 

[tattoodrob]

1 hour ago, Damrongsak said:

I would check voltage drop at the meter/incoming line and at the point of delivery to the heavier appliances.  Putting in a step-up transformer is not a good cure for small house wiring.  Small gauge wires contribute to voltage drop and subsequent heating of the house wiring.  The more current you draw, the greater the voltage loss.

 

When I lived in Thailand, I had to heat water in the cold season in Loei.  I put a 5 gallon wash tub out in the sunny part of the yard and covered it with a bus window conveniently left by the former tenant.  By 4 pm the water and air were warm enough to "shower" with, using a dip ladle. I did have a small transformer, but that was so the single fluorescent light had enough voltage to light up in early evening.  The other couple of incandescent bulbs would work just dim.  I did have a fan and radio.  I recall one electric bill was about 5 Baht for the month.

 

 

wow......thats good for you...i dont think my family could live like that.

Why did you have  a transformer if had electric supply ? i know nothing about electric but didnt know needed a transformer if had some electric supply and didnt have much to power or do you mean you had a  generator?? 

Anyway what would you suggest in my situation then when requiring more power to live in this heat with other people staying with me and needing/wanting aircon/hot showers  etc?

[Crossy]

3 hours ago, RichCor said:

Question for @Crossy,

Installing an AVR, isn't it functioning as an isolating transformer creating questions on how an RCD, placed upstream or downstream, will function? And how to deal with where Neutral and Earth-Ground and how/where they are potentially bridged.

 

They are invariably auto-transformers for cost and size reasons, no isolation.

 

The neutral is bridged straight through from in to out.

 

 

[Crossy]

3 hours ago, RichCor said:

 Appears this may be a 3-phase CU being used as a single-phase CU.  Which is neither here nor there, just interesting.

 

Evidently the original installer thought that 3-phase was going to be needed.

 

There are a LOT of 32A breakers in there, I wonder what they are for.

[Crossy]

3 hours ago, Damrongsak said:

I would check voltage drop at the meter/incoming line and at the point of delivery to the heavier appliances.  Putting in a step-up transformer is not a good cure for small house wiring.  Small gauge wires contribute to voltage drop and subsequent heating of the house wiring.  The more current you draw, the greater the voltage loss.

 

You are of course correct in your assertions.

 

What would your solution be?

[wayned]

Wrecking ball and start over?

[RichCor]

10 hours ago, Damrongsak said:

I would check voltage drop at the meter/incoming line and at the point of delivery to the heavier appliances.  Putting in a step-up transformer is not a good cure for small house wiring.  Small gauge wires contribute to voltage drop and subsequent heating of the house wiring.  The more current you draw, the greater the voltage loss.

 

On 5/7/2017 at 8:58 PM, tattoodrob said:

No multi meter. i presume loss of volts is after the meter and is worst when turn on showers then drops the most and lights dim,fans go slower etc.especially if a few items on together.....can hear the aircon drop speed when turn on high current items.

 

OP, before you go dropping money on that AVR hardware, as @Damrongsak suggests, some baseline measurements should be taken so you can properly spec your potential solution.

 

I'd suggest having a sparky help you find the following:

Diameter size and length of wire running from Electric Meter to CU

Voltage measurement at Electric Meter (with power turned OFF)

Voltage measurement at Electric Meter (with power turned ON)

Voltage measurement at Electric Meter (running heavy appliance)

Voltage measurement at Electric Meter (running multiple heavy appliances concurrently)

Voltage measurement at CU (with power turned OFF) [should be similar to Electric Meter measurement]

Voltage measurement at CU (with power turned ON)

Voltage measurement at CU (running heavy appliance)

Voltage measurement at CU (running heavy appliances concurrently)

 

...so OFF, Nominal, HIGH, and HIGHEST usage.

 

Then post the findings here.

 

Different AVRs have range of operation over which they can compensate. So knowing what your current requirements are will help you select one that works for your situation.

 

 

 

 

 

 

[tattoodrob]

9 hours ago, wayned said:

Wrecking ball and start over?

would that give me better power supply!!!!!

 

[tattoodrob]

9 hours ago, Crossy said:

 

Evidently the original installer thought that 3-phase was going to be needed.

 

There are a LOT of 32A breakers in there, I wonder what they are for.

Wife says some are water heaters,some for oven/hob ..some are air con,some are lights!! i have 2 chandaliers and many lights around property wall etc.

 

[tattoodrob]

1 hour ago, RichCor said:

 

 

OP, before you go dropping money on that AVR hardware, as @Damrongsak suggests, some baseline measurements should be taken so you can properly spec your potential solution.

 

I'd suggest having a sparky help you find the following:

Diameter size and length of wire running from Electric Meter to CU

Voltage measurement at Electric Meter (with power turned OFF)

Voltage measurement at Electric Meter (with power turned ON)

Voltage measurement at Electric Meter (running heavy appliance)

Voltage measurement at Electric Meter (running multiple heavy appliances concurrently)

Voltage measurement at CU (with power turned OFF) [should be similar to Electric Meter measurement]

Voltage measurement at CU (with power turned ON)

Voltage measurement at CU (running heavy appliance)

Voltage measurement at CU (running heavy appliances concurrently)

 

...so OFF, Nominal, HIGH, and HIGHEST usage.

 

Then post the findings here.

 

Different AVRs have range of operation over which they can compensate. So knowing what your current requirements are will help you select one that works for your situation.

 

 

 

 

 

 

i dont have a lot of choices for my solution so even with all these figures then is mean what..i dont buy an avr or ?? 22kv seems like right or ok choice for my house.....i cant even get sparky to come around to fix stuff now let alone tell him i want just take some measurements....what will happen if i buy 22kv..you think not strong enough or?? i dont mean to be awkward..just want sort problem out with out getting too deep and asking Thai sparkys here too much as they dont know much!!

[Crossy]

In reality @RichCor is correct, before investing in a solution one needs to be sure of the problem.

 

As a minimum you could go and buy a cheap multimeter and make some checks at you distribution board. Measuring at the meter may be harder as it could be sealed.

 

Assuming to drop is BEFORE the meter (i.e. on PEAs patch) then the ideal solution would be a transformer, but it will cost $$$. The AVR is a far cheaper, but likely less effective, solution.

 

If the drop is AFTER the meter then you have other options, potentially even lower cost. But of course we need to know exactly what's going on.

 

Any chance of those photos of the units with the lids off? It's even possible there's mis-wiring causing your issues.

[RichCor]

12 minutes ago, tattoodrob said:

i dont have a lot of choices for my solution so even with all these figures then is mean what..i dont buy an avr or ??

 

You certainly don't want to put in something as a solution that may burn your house down.

 

Knowing the cable size and length will tell us if your cable is undersized (as your original sparky planned the CU for a 3-phase service and you're currently getting by on single-phase, so the MAINS Wiring is already underspec'ed by 200%).

 

Installing an AVR will stress those two wires even more (pulling more amperage over them to use to shore up the voltage).  

 

It may mean you also need to replace your current MAINS wires from the Electric Meter to the CU with a larger diameter wire capable of handling the electrical load.

[Damrongsak]

19 hours ago, tattoodrob said:

Why did you have  a transformer if had electric supply ? i know nothing about electric but didnt know needed a transformer if had some electric supply and didnt have much to power or do you mean you had a  generator?? 

Anyway what would you suggest in my situation then when requiring more power to live in this heat with other people staying with me and needing/wanting aircon/hot showers  etc?

I had a manually operated multi-tap transformer.  Some evenings the voltage would sag so badly that you could barely read from the light of a lightbulb.  Fluorescent lights wouldn't even light up. Had to turn up the transformer and then as voltage came back up later, the unit would alarm and I would turn it down a step at a time.  But it was just a small wall-mount unit.

 

It all comes down to having an adequately sized service AND making sure the conductors are properly sized for the load and distance from the source.    Note that motor loads like your air conditioner compressors will draw more current at lower voltage, thus compounding the line loss problem.  Perhaps transformer(s) on some loads would help.  I would just wait until one or more air con units cycle off and turn them off while I showered.  I'm assuming the water heater is an on-demand type, and they suck a lot of juice. 

[RichCor]

The 'other' alternative would to install an electric generator with a transfer switch, or a field full of Solar Panels and bank of batteries.

[tattoodrob]

9 hours ago, Crossy said:

In reality @RichCor is correct, before investing in a solution one needs to be sure of the problem.

 

As a minimum you could go and buy a cheap multimeter and make some checks at you distribution board. Measuring at the meter may be harder as it could be sealed.

 

Assuming to drop is BEFORE the meter (i.e. on PEAs patch) then the ideal solution would be a transformer, but it will cost $$$. The AVR is a far cheaper, but likely less effective, solution.

 

If the drop is AFTER the meter then you have other options, potentially even lower cost. But of course we need to know exactly what's going on.

 

Any chance of those photos of the units with the lids off? It's even possible there's mis-wiring causing your issues.

will try and take some pics,just dont like messing with it.lets presume i got normal size wires that all(most )Thai sparkys would use to wire a house..i got underground electric cable from the meter as didnt want over ground and my builder moaned as that costs more as higher spec and runs about 30 meters to the box.

Surely its just as dangerous to be running items now with little volts as electrical items straining(running slow/dimming etc) as it is with the extra volts/power from the AVR .....or not,i think i read somewhere here that when running electrical items underpowered then they get hotter quicker and chance of failures so its quite confusing as now seems putting in AVR is potentially dangerous too...so what do i do..in ideal world then yes a real sparky would/could come around to check/fix etc but i dont think my house wired wrong as a few sparkys seen my box etc and not mentioned anything and they are all not experts so all wire same sort of way i expect so even if mine wired wrong then not easy to find someone to correct it .

i would really presume my house /phase not getting enough power for all the stuff i got as i live out of the main town where older houses  are etc and PEA know there transformer shit here as more or less said so and so i cant get enough power to have the many items on at the same time but sometimes i cant avoid that so if i have normal sized wires and not enough power coming in from PEA line then is ok or not to put AVR?..i understand all should be checked first but thats looking not to be easy so what im saying is shall i buy the AVR box or not?.......i want to try help the situation but its getting hard work with all this info i need to  get and do before knowing will be ok or not.

If my supply not strong and ive got normal wiring then can you recommend the AVR or still not good idea and better i just put up and carry on with air cons not working to full capacity when many on and dim lights while people shower???

Your all being very helpful and i appreciate it but you all know more than any sparky i can get to work /help me.....i bet most Thai sparkys here never seen or wired  in an AVR.......2 days  now the sparky i use who seems fairly knowledgeable for a thai doesnt even answer his phone after multiple calls..this is Thailand,hard to do things properly here often.

If its very dangerous to install the AVR then i wont but if all should be ok then i will..i know no one want to commit without knowing full knowledge of my power measurements ,cable sizes etc but an educated guess would be very helpful to me as i cant afford a transformer at that price so either AVR or nothing!

Thanks.

 

 

[wayned]

Exactly where do you live?  Maybe one of us that claims that we know more than the average Thai sparky could pop on by and give you a fair evaluation of your situation and how to improve it.  Although beware, our services might cost you a cold one!

[Crossy]

@tattoodrob please help us to help you, never assume anything (particularly here), popular engineering term "assume, makes and ass out of u and me".

 

Without concrete data we can only surmise, what we are surmising is that you have a common problem but it may not be a correct surmission. The issue with your hot-tub pipes may be a clue to something more serious.

 

We still don't actually know what 220V wires you have at the road, no photos yet.

 

We just don't want you shelling out on hardware which may not fix your issue.

 

As Wayned suggests, let us know where you are (within say 20km) maybe one of us is close enough to drop round for a beer or two

 

 

[tattoodrob]

6 hours ago, Crossy said:

@tattoodrob please help us to help you, never assume anything (particularly here), popular engineering term "assume, makes and ass out of u and me".

 

Without concrete data we can only surmise, what we are surmising is that you have a common problem but it may not be a correct surmission. The issue with your hot-tub pipes may be a clue to something more serious.

 

We still don't actually know what 220V wires you have at the road, no photos yet.

 

We just don't want you shelling out on hardware which may not fix your issue.

 

As Wayned suggests, let us know where you are (within say 20km) maybe one of us is close enough to drop round for a beer or two

 

 

Pranburi near Hua Hin is my location.my laptop camera is so shit that i have to use my mrs ipad to take any decent pics but will try today take some with my laptop and hope ok.The hot tub issue was a long time ago now and have rcd fitted since and only happened on those 2 occasions that had power cut from PEA line.

[tattoodrob]

Hope these pics help....first pics show outside and can see my wires and neighbours come from lower pea lines and then across road to the pole then down to meter then through underground pipe as shown,if that top 3 line is 3 phase then they wont let me use it!

 

[RichCor]

Nicely dressed, even with the Mains incomer being jumpered over to the Safe-T-Cut.

Noticed the color reversal on the B/W circuits (but angry pixies don't care), just hope they're wired appropriately on the other end.

 

Not a lot of support of Ground Wires in there, so very good you have the Safe-T-Cut.

And can't see what color the Neutrals are for the Red and Blue circuit wiring.

Edit: ...or the Neutral return for the Swimming Pool? (Circuit #2, top right).

 

If you don't mind saying, what is your kW usage billed per month?

 

 

[Crossy]

I'm wondering if those wires on the ground bar are actually grounds, or has someone used it as extra neutrals?

 

No evidence of a ground rod connection on there.

 

 

[Crossy]

We could do with a look in the Safe-T-Cut too, I'm looking for a MEN link.