Explain transformer or other options

[tattoodrob]

Ok i read a few threads and still confused..AVR,MEN etc is all foreign to me....i have no knowledge of electrical stuff so please explain in very simple terms without sparky talk ......when i or whoever turns on the shower etc then often lights dim and stay dim till showering finished..if open more than 1 air con then they obviously work at less then 100% as can hear they slower and so less efficient....talked to electric board before and Thai sparkys and say i need a transformer.........electric board will sell me one for 200k baht or more......is there any cheaper options??? ..seems a lot for just running air cons etc

I live in between 2 main towns but not many houses around so im guessing im on one phase not that i understand the difference in one phase/3 phase .....and we share this line with all the other houses around ...my house fusebox is about 40m from line at the road.....a neighbour behind who is about 200m from the line had to install all the posts and a transformer.......is the transformer the only answer as when have 4 air cons on and take a shower its awfull....all lights very dim,fans run slow etc..............i have a lot of things to run: pool pump ,many lights ,tvs etc.......my wife said can buy the transformers second hand somewhere she was told........who would/could install it if found one...why the hell are they so expensive?? what are my options if any ? thanks......ps keep it simple...very simple.......i believe my house is wired up correctly and this problem been ongoing years but now i have more people living with me then is more noticeable,as just about bearable before but now its really hot and would like my air con and others working at full power.

Would an AVR help me? could i try and get another line put in somehow so i have 2 lines like 2 separate houses would have..i could pretend im building new house behind then connect to my fusebox? it would be more expensive but if it helped when i  needed it then would be ok.....when hot nd house full thenmaybe could use both?? ......would that help? any ideas on a cheaper solution than a transformer would be good but no one i have spoke to electrically here in Thailand can help with cheaper solution so far.

 

[wayned]

IMHO a transformer is your best, option, but 200k seems a little expensive.  The first thing you need to determine is if your house is on single phase or three phase.  It's easy to do,. Look where the wires enter your house, if there are two wires, it's single phase, if there are four it's three phase.  The 200k is probably for a three phase transformer. Ff you are on single phase there is no need for that and you should go back to PEA and asked about a single phase transformer.

 

Remember once you buy the transformer and it is installed on the PEA pole, it becomes the property of PEA!

[Crossy]

Whilst you're out looking at wires, take a look at the poles in the road. Do they have three wires right at the top on large insulators? These would be the 25kV supply needed if you get your own transformer.

 

Also what size meter do you have? Look at the front plate, it will be marked 5(15), 15(45) or 30(100).

 

Do you have a multimeter, it's handy to have some numbers to look at when determining a solution.

[tattoodrob]

18 hours ago, wayned said:

IMHO a transformer is your best, option, but 200k seems a little expensive.  The first thing you need to determine is if your house is on single phase or three phase.  It's easy to do,. Look where the wires enter your house, if there are two wires, it's single phase, if there are four it's three phase.  The 200k is probably for a three phase transformer. Ff you are on single phase there is no need for that and you should go back to PEA and asked about a single phase transformer.

 

Remember once you buy the transformer and it is installed on the PEA pole, it becomes the property of PEA!

i got single phase..it was the PEA who initially quoted me the discounted price of 180 k baht at the time 4 years ago and they knew what i needed so knew must be one phase they quoting me for,in main town some people paid 300000 bt for the transformer.....he said originally they will probably upgrade there own transformers on the road but never did.

If i bought a transformer then would ask for the pole to be put in my land or no buy..all the neighbours would join for free!! so no deal if that the case....

 

[tattoodrob]

13 hours ago, Crossy said:

Whilst you're out looking at wires, take a look at the poles in the road. Do they have three wires right at the top on large insulators? These would be the 25kV supply needed if you get your own transformer.

 

Also what size meter do you have? Look at the front plate, it will be marked 5(15), 15(45) or 30(100).

 

Do you have a multimeter, it's handy to have some numbers to look at when determining a solution.

I will check the meter tomorrow and let you know what plate says...im 99% certain no 3 wires/large insulators so 1 phase.....whats my options??

 

[tattoodrob]

14 hours ago, Crossy said:

Whilst you're out looking at wires, take a look at the poles in the road. Do they have three wires right at the top on large insulators? These would be the 25kV supply needed if you get your own transformer.

 

Also what size meter do you have? Look at the front plate, it will be marked 5(15), 15(45) or 30(100).

 

Do you have a multimeter, it's handy to have some numbers to look at when determining a solution.

Hello,

yes there is a pole with 3 wires going along road and i have 15/45 written on my meter and says single phase with 2 wires....whats my options?

 

 

[wayned]

IMHO,  if there is 26kva available, you could get PEA to mount a transformer on the pole where the meter is  mounted.  Since your supplt is only single phase You do not need a large, and expensive, three phase transformer, you only need a single phase one.  The 15/45 meter should be okay.  Yopu should ask PEA the cost of a single phase transformer and see if they will sell you that instead of the three phase.  They are continually upgrading the small village supplies and should have many "used" ones laying around.

 

However your statement that there is 3 wires on the pole going along the road doesn't actually confirm that there is 25kva available.  There should actually be two sets of three wires.  The pole needs to be the higher pole with two sets of three wires, the lower set will be attached to the side of the pole and the input of your meter  will be connected to one of them.  Then there should be another set at the top of the pole normally on a horizontal spreader, those are the 25kva lines and are what the transformer needs to be attached to.

 

It should look something like this with the wires on the horizontal cross bean near the top of the pole.  They are the 25kva wires need for the transformer.  The lower voltage distribution wires are connected to the output of the transformer and go to the meter. I can't seem to attach the picture so I've posted a link to a word file.  Maybe Crosssy will fix it like he did for me the last time.

 

power distribution.doc

[tattoodrob]

yes Wayned there is long pole with 3 larger horizontal wires and lower residential wires ......the nearest transformer is about 100 m or a bit more away......will having a transformer closer really help a lot as i guess after i buy one then others will join as pole my meter is on i already share with a neighbour and its not on private land so what is to stop others nearby asking to join on then im back to square 1 again?? or not?..anyway will that sort out my problem completely? ..maybe i can ask to put on a new pole on my land so others not join.thanks

[tattoodrob]

Update: phoned the local electric board and was quoted 250 k baht for a single phase transformer,no second hand ones!!!! Crazy.

Had an idea ..would getting another main line put in help so have a line as usual and extra as booster when needed,maybe the  extra line for air cons and water heaters when my house full and other line for the all of house as usual ..would this work and how can connect 2 main lines like that,would be good if could add switch so only use second line when need it.....to get another line and meter then i might bullshit and say im building in the back of my land as i have some empty land behind my plot and get the temporary meter fitted near my meter.....is it possible to wire it in like i want so only as a booster when needed......the temp electric is more expensive i think but take a long time to get bill up to 250k baht and would only use sometimes so wont be too bad...what do you knowledgable guys think of my idea.

[Crossy]

Assuming there is 3-phase at the pole (4 "residential" wires) the next best solution would be to install 3-phase to your house. You would need to re-wire a bit and get a new distribution board but it would cost a lot less than 250k.

 

If no 3-phase then an AVR (Automatic Voltage Regulator) would be a reasonable solution, probably about 30k.

 

 

[wayned]

Prices must have really risen.  About 15 years ago I was  contemplating building a large farm equipment repair facility and machine shop next to my house.  Since I would have needed a dedicated 3 phase supply I went to PEA and got a quote about running the 25kva lines to my property and installing a transformer.  They quoted 197,

500 baht, but that included setti8ing 7 large poles, the wires and the transformer as the high voltage only runs through the village on the crossroad.  I never built the building so the deal was never struck.

[tattoodrob]

On 5/4/2017 at 5:17 AM, Crossy said:

Assuming there is 3-phase at the pole (4 "residential" wires) the next best solution would be to install 3-phase to your house. You would need to re-wire a bit and get a new distribution board but it would cost a lot less than 250k.

 

If no 3-phase then an AVR (Automatic Voltage Regulator) would be a reasonable solution, probably about 30k.

 

 

definitely no 3 phase here..where can buy an AVR and how much would it help?

 

[tattoodrob]

On 5/4/2017 at 7:20 AM, wayned said:

Prices must have really risen.  About 15 years ago I was  contemplating building a large farm equipment repair facility and machine shop next to my house.  Since I would have needed a dedicated 3 phase supply I went to PEA and got a quote about running the 25kva lines to my property and installing a transformer.  They quoted 197,

500 baht, but that included setti8ing 7 large poles, the wires and the transformer as the high voltage only runs through the village on the crossroad.  I never built the building so the deal was never struck.

prices change on who you talk to and how much they think they can get but no one does at a reasonable price so is better an AVR or put a temporary meter?and so would have extra line that i can use so have 2 main lines coming in as im not paying around 250k baht for a single phase transformer!

 

[tattoodrob]

On 5/4/2017 at 5:17 AM, Crossy said:

Assuming there is 3-phase at the pole (4 "residential" wires) the next best solution would be to install 3-phase to your house. You would need to re-wire a bit and get a new distribution board but it would cost a lot less than 250k.

 

If no 3-phase then an AVR (Automatic Voltage Regulator) would be a reasonable solution, probably about 30k.

 

 

so is AVR better than having a temp meter (extra line) put in ? as both would cost around the same i think by the time i get new fusebox and pay the electrician to put lines in from the temp meter and wire up properly

[wayned]

1 hour ago, tattoodrob said:

definitely no 3 phase here..where can buy an AVR and how much would it help?

 

I'm confused.  Look what you said in post eight.  "There are three larger horizontal wires and lower residential wires", the larger horizontal wires are 25kva and would need a transformer to provide power to your house.  How many residential wires are there on the pole, the ones that come from the transformer 100 meters away.  If there are four, three insulated and a forth on the top, normally not insulated, then you have three phase to the pole.  You would then only need PEA to change the meter to a three phase meter, run new wires from the meter to your house and rework your CU and power distribution to accept a three phase supply.

[impulse]

For about $8, I bought one of these plug-in volt meters  that tells me what's going on with my household voltage.  I'm sure I bought mine in Chinatown in BKK, but they can be had online at AliExpress and probably Lazada.  The information would be helpful in figuring out just how bad  your problem is, and whether it's really getting worse.  And it doesn't require any sparky skills or safety issues like a VOM does.  Just plug it in and leave it plugged in.

 

https://www.aliexpress.com/item-img/AC-80-300V-Power-Voltage-Monitor-Meter-LCD-Voltmeter-Household-Factory-Switch-Flat-Plug-AC-Voltage/

 

 

Caveat:  You may find one cheaper than this link...

 

[tattoodrob]

10 hours ago, wayned said:

I'm confused.  Look what you said in post eight.  "There are three larger horizontal wires and lower residential wires", the larger horizontal wires are 25kva and would need a transformer to provide power to your house.  How many residential wires are there on the pole, the ones that come from the transformer 100 meters away.  If there are four, three insulated and a forth on the top, normally not insulated, then you have three phase to the pole.  You would then only need PEA to change the meter to a three phase meter, run new wires from the meter to your house and rework your CU and power distribution to accept a three phase supply.

i have been told only one phase available all around here by electric company.....the small old government transformer supplies all the houses in my area.If there is 3 phase then he didnt tell my wife and quoted 250k baht for the transformer (one phase he said but maybe is 3 phase)and 2 poles etc........so my question is will AVR help or  better to get the extra meter and line and join to my air cons/hot water heaters to that line or half of them maybe?

[Crossy]

If it's volt drop on the run to your meter a second supply will make no odds whatever.

 

An AVR will improve matters significantly, just how significantly depends on just how much voltage droop there is, you'll need to do some measurements to determine that. Do you have a multimeter?

 

Please post a photo of the power pole where your meter is, make sure we can see all the wires at the top. We can then determine just what you have at the road.

[tattoodrob]

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.

Meter says one phase as mentioned before and if had 3 phase around then im sure i would have been offered it at the beginning........so if power drops from after the meter then is a new extra line better ?

Never seen this AVR in any builders shops here.

 

[tattoodrob]

this not my pic but i have similar to this running along the road but our line comes from the lower lines that already gone through small old PEA transformer and run to everyones houses.

The neighbour further behind me about 500m has electric from the top lines as pictured and run along on poles along the road all the way to his house and transformer,he paid a lot of money for that and i think other near neighbours joined from his line after transformer.

So if that line along my road is 3 phase then they not offering it to anyone here.....i was told long time ago that would upgrade there transformers but they never did so now have more and more houses sharing and more noticeable problem for me now as my house full so air cons on etc and all not working full power and lights dim everytime someone shower .

 

[RichCor]

You could always ask PEA to measure the three available lines (phases) and see if you'd benefit from being assigned to one of the other two available phases.

 

Customer use of the transformer is supposed to be 'balanced' among the three available LIVE phase wires, each household connected to only one or sometimes all three phase lines in an attempt to keep the draw equal among the wires the majority of the time. But this isn't easily done as you can't predict what each household will connect and run, or run at what time, in a given house. Or even predict that society needs might change and suddenly big screen TVs and Air Conditioners are a must-have thing. 

 

So you might benefit from being switched over to one of the other available phase lines.

Or even going to a 3-phase meter and splitting your house up as if it were three houses to lessen the overall power load on one phase. Are you sure the PEA said they won't issue 3-phase meters?

 

If the transformer is just over-utilized, then your community might benefit from requesting a larger capacity transformer be put in its place.  But if this isn't going to happen for a long while, or if ever, then looking into an AVR might be the thing to do. An AVR works by boosting the line Voltage by pulling and converting from the available Amperage (as in: voltage x amperage = wattage).  Many, many stories of people installing AVRs here on ThaiVisa.

[wayned]

If you look at the transformer in the picture, it is a three phase transformer, the input has three separate connections to the three high voltage lines.  If the old transformer in your village has the input connected to the three lines then it is a three phase transformer and the residential lines connected to it are three phase.  There should be three insulated residential lines and a forth that is the neutral which might not be sheathed.

 

So if that is what you have, three phase is available and the statement by PEA that "no one has three phase " is most likely also true as all the connections to the existing houses are only connected to one of the phases so every one has a single phase connection.  If there is three phase then you "should" be able to install a three phase meter,  but PEA's  reluctance to you doing that is most  likely due to the fact that they already know that the current transformer is "maxed out" and having you buy and install another on their lines is a cost effective solution.

 

Good luck as it seems that they have you between a rock and a hard place.

[tattoodrob]

i have been told that there is no 3 phase available where i live!!! and my only option is to buy there expensive transformer.my wife spoke to them and asked any oher options..answer NO.

yes there are probaly things they could do to help but either dont know or no money in it for them but selling me 2 large poles and transformer and installation probably gives them a great pay day..other options not worth it to them.

[tattoodrob]

i think  im going to have to try AVR route so next question is how big and where place it....should i get 10kva or 15,......i have water pump,8 aircons but probably 5 run most at one time,plus 5 hot water heaters ..hopefully never running all at same time,5 flat screen tvs,sometimes 3 or 4  of them on at same time air cons..loads of lights with normal type bulbs,pool with pump on nearly all day.

So if i buy AVR then which best and how to wire in......between meter and fuse box?,i have a seperate rcd..do i have to buy anything else or just the AVR ? thanks in advance,as mentioned before i know nothing about electrics so keep it simple,thanks

[wayned]

I'm sure that Crossy will be along and discuss the AVR size and installation.  I have absolutely "zero" experience with them.  After reviewing all of the items that you have in your house I can see why PEA wants you to install your own transformer.  If you turn them all on at the same time you probably make the lights dim in the nearest big town.  I'm surprised that they don't want you to build your own power plant!

[Crossy]

@tattoodrob I see you have a 15/45 meter, what value (Amps) is your incoming breaker?

 

You're probably pushing the supply anyway and your AVR will be working quite hard.

 

Thus I suggest going for a 20kVA unit.

 

A 15kVA would likely be OK if it was actually capable of 15kVA continuously, but one doesn't want to push the envelope, these things (like much in the modern world) are going to be "optimistically" rated.

 

By the way, these units have cooling fans, you may not want it in your lounge.

 

Since you have a separate front-end RCD (I'm assuming a Safe-T-Cut or similar), you can wire the AVR between it and the distribution board, meaning you only need to buy cable. I would also add cheap analog meters for Volts and Amps so you have some idea of what you're doing to your poor meter and can throttle consumption a bit if it looks like your going to stress things.
 

[tattoodrob]

15 hours ago, wayned said:

I'm sure that Crossy will be along and discuss the AVR size and installation.  I have absolutely "zero" experience with them.  After reviewing all of the items that you have in your house I can see why PEA wants you to install your own transformer.  If you turn them all on at the same time you probably make the lights dim in the nearest big town.  I'm surprised that they don't want you to build your own power plant!

Haha yes sounds bad but really rarely have more than 1 or 2 aircons on at a time and then is just about ok but now really hot and have people stay with me more often so is chance of more aircons being on and showers and so pump too ......PEA dont know about how many aircons etc as didnt disclose that info fully as maybe want 500000 bt+ for the transformer but seriously even when just my family here and nothing much used then often lights dim when someone showers or flickers when pump opens.......wasnt good when i moved to the sticks 5 years ago but plenty more houses around now and no upgrades  to the line or transformers.

 

[tattoodrob]

14 hours ago, Crossy said:

@tattoodrob I see you have a 15/45 meter, what value (Amps) is your incoming breaker?

 

You're probably pushing the supply anyway and your AVR will be working quite hard.

 

Thus I suggest going for a 20kVA unit.

 

A 15kVA would likely be OK if it was actually capable of 15kVA continuously, but one doesn't want to push the envelope, these things (like much in the modern world) are going to be "optimistically" rated.

 

By the way, these units have cooling fans, you may not want it in your lounge.

 

Since you have a separate front-end RCD (I'm assuming a Safe-T-Cut or similar), you can wire the AVR between it and the distribution board, meaning you only need to buy cable. I would also add cheap analog meters for Volts and Amps so you have some idea of what you're doing to your poor meter and can throttle consumption a bit if it looks like your going to stress things.
 

Thanks for your help...........Global house has some AVR s ,lio brand or something like that from vietnam......my breaker box is in a small utility room outside so thats good right.....my rcd was put in long time after my breaker box was put in but see 2 wires come out large breaker box to the nano safe t cut RCD then go back in again to the top of the box.

The AVR has some dials on it referring to volts in and out,really big and heavy box the AVR!

I think my breaker is 30 amps as seem to remember hearing something like that from the sparkys back when it was fitted.

AVR will be ok on the floor right,does it get really hot as room not ventilated but room is not in direct sunlight so not an extremely hot room usually but i could leave door open if think it necessary for more air around.

so lets see if i understand this AVR........it seems to steal(paid for by me) more power from outside line when i need it? what about other peoples houses then when my avr is operating,they get less power or it is like a mini transformer inside and boosts my input when needed??..but then i read that my electric bill may go up so i must be getting more from the line outside in that case?

Will it work usually only when i have a lot of strain or even when i got just 2 air cons on as still maybe needed then and if no air cons etc just tv then it doesnt operate or help ? so is it always operating but just at different levels right?

would i need to turn it off when not at home or when on holiday or just leave it as it is ?

will it stop lights dimming/flickering after fitted and keep all aircons at there full power ?..or will just help so not so noticeable problem?

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 ?

sorry about all the questions,hope you can answer for me ..the workers at Global have no clue on all this.

AVR also has a 110v switch so i guess thats for other countries and never use that here for anything.

Where could get an amp dial like you mentioned as not seen in any shops here....ebay?? or ?

thanks in advance.

 

 

 

 

 

[tattoodrob]

Sorry..one more question.........when i had some power cuts before then seems i may have had some sort of high surge as 2 times before in last few years after power cut and started again then i had some burnt water lines from hot water box to jacuzzi in bathroom..metal flexible water pipes i believe used for the hot water lines to the showers/jacuzzi as water heater is in the roof space and is a multi line heater so use for 2 showers and the jacuzzi in one room..i guess some one could have been electrocuted if was using shower or jacuzzi at the time..this why i then fitted the RCD safe t cut as didnt realise the breaker box was not going to stop an electroction and trip first!!

i contacted the electric company after happened second time and they said nothing to do with them..thya said is my house so very strange happened twice at powercut time!! ..anyway rcd fitted.

so question is will the AVR protect the house from any high surge or is not quick enough to catch it and reduce it to safer level........and i guess my rcd would trip anyway now if surge/short happened if anyone having a shower.....i thought fuses were for saving people from eletrocution but they are not are they?

thanks for any answers.

[Crossy]

The AVR has some dials on it referring to volts in and out,really big and heavy box the AVR!

The AVR is a variable transformer, transformers have lots of iron in the core, they are heavy, nothing you can do about that.

 

I think my breaker is 30 amps as seem to remember hearing something like that from the sparkys back when it was fitted.

The breaker will have the current rating marked somewhere, the "30" is likely the 30mA leakage trip current.

 

AVR will be ok on the floor right,does it get really hot as room not ventilated but room is not in direct sunlight so not an extremely hot room usually but i could leave door open if think it necessary for more air around.

It will get warm, but transformers are pretty efficient, best to see how it goes and add room ventilation if needed. It will be fine on the floor, but do watch for possible flooding, maybe jack it up on blocks.

 

so lets see if i understand this AVR........it seems to steal(paid for by me) more power from outside line when i need it? what about other peoples houses then when my avr is operating,they get less power or it is like a mini transformer inside and boosts my input when needed??..but then i read that my electric bill may go up so i must be getting more from the line outside in that case?

It doesn't exactly "steal" power, it's just a transformer so Power Out = Power In, in simple terms Power is Volts x  Amps, so if the voltage is low more Amps are needed for the same power. You may see a change in your bill due to your appliances now working at their proper efficiency. It may affect others by pulling the voltage even lower, but that may spur the PEA to actually upgrade the village transformer.

 

Will it work usually only when i have a lot of strain or even when i got just 2 air cons on as still maybe needed then and if no air cons etc just tv then it doesnt operate or help ? so is it always operating but just at different levels right?

It adjusts itself to the incoming supply continually, maintaining a constant output voltage.

 

would i need to turn it off when not at home or when on holiday or just leave it as it is ?

will it stop lights dimming/flickering after fitted and keep all aircons at there full power ?..or will just help so not so noticeable problem?

Just leave it alone, no need to turn off when not home. You will see a significant improvement in your lighting and A/C operation, it won't stop the flicker when a big load comes on, but the dimming issue will go away. Just how well it works will depend upon just how bad the incoming supply actually is.

 

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.

 

AVR also has a 110v switch so i guess thats for other countries and never use that here for anything.

Do not touch the 110V switch, put some tape over it so others don't play.

 

Where could get an amp dial like you mentioned as not seen in any shops here....ebay?? or ?

Ours came from MegaHome but anywhere which specialises in electrical stuff should have them, I'm sure I've seen them in Global. Take the photo with you.

 

when i had some power cuts before then seems i may have had some sort of high surge as 2 times before in last few years after power cut and started again then i had some burnt water lines from hot water box to jacuzzi in bathroom..metal flexible water pipes i believe used for the hot water lines to the showers/jacuzzi as water heater is in the roof space and is a multi line heater so use for 2 showers and the jacuzzi in one room..i guess some one could have been electrocuted if was using shower or jacuzzi at the time..this why i then fitted the RCD safe t cut as didnt realise the breaker box was not going to stop an electroction and trip first!!

Damaging flexible water pipes is very worrying, it indicates that there are large diverted neutral currents going somewhere, but if your system is correctly wired (either TT or MEN) the current should be going down the ground rod, not through the jacuzzi pipes. You should really get everything checked by a competent electrician who knows what MEN and TT are (you'll need good luck to find one I'm afraid). Do verify that you have a ground rod and that it is actually connected.

 

i contacted the electric company after happened second time and they said nothing to do with them..thya said is my house so very strange happened twice at powercut time!! ..anyway rcd fitted.

An open neutral may lead to the symptoms you describe.

 

so question is will the AVR protect the house from any high surge or is not quick enough to catch it and reduce it to safer level........and i guess my rcd would trip anyway now if surge/short happened if anyone having a shower.....i thought fuses were for saving people from eletrocution but they are not are they?

The AVR won't protect from very fast high-energy surges (lightning) but it ought to be quick enough to protect from the phase imbalance caused by an open neutral. Fuses are there to protect the installation, not necessarily the people.