PEA - Information about existing house connection. Is it 5 or 15 Ampere?

[Oldie]

Does anyone know how I can find out if a house connection is 5 or 15 Ampere? Is there any information for instance on the bill or somewhere else? So far I could not find anything.

[lopburi3]

It will be on the meter - 15 amp would read 15/45

[Oldie]

14 minutes ago, lopburi3 said:

It will be on the meter - 15 amp would read 15/45

I guess this number has a different meaning - how accurate the meter is (the ampere where it got tested) and the maximum ampere it can handle without any problems. Before I had an analog 15 (45) meter. My new electronic meter is 5 (100). I hope that I understood this correctly. There is a lot of unclear information on the Internet. 

[lopburi3]

12 minutes ago, Oldie said:

My new electronic meter is 5 (100).

Have no idea what that means but if you had 15/45 meter before it should be `15 amp service (main fuse probably 66 amps or so)

[Oldie]

7 minutes ago, lopburi3 said:

Have no idea what that means but if you had 15/45 meter before it should be `15 amp service (main fuse probably 66 amps or so)

Then the 5 (100) would not make sense anymore. It stands for 5/100 instead of 15/45 before. It would be a downgrade to 5 ampere. 

The main fuse is 63 ampere. And here the problem started. A friend of mine has the same and she was told by the electrician that he cannot install a new water heater because she has only a 5 ampere connection and combined with 4 aircons this would be too much for 5 ampere - what I understand. But is he correct with the 5 ampere? It should be written somewhere on the bill but I couldn't find anything. A lot is in Thai. 

[lopburi3]

Am sure the 5/100 just means the digital reading is accurate in that range (one meter fits all now) but 63 amp main fuse would indicate 15 amp service.  Am sure the tech had never seen that type of meter and is thinking the old analog system.

[Crossy]

Yeah, the 5(100) electronic meters are "one size fits all" and maintain accuracy to (and beyond) 100A. The numbers really don't mean anything as to the supply "size" any more.

The mechanical meters are calibrated at the smaller number, the larger number being the maximum current.

The mechanical meters are incredibly robust and won't die even with a continuous 100% overload, they will however lose accuracy (bet they don't read low). 

[Oldie]

This all seems to be confusing. So I called PEA. No idea why such an important information is not written down anywhere. First a lady told me that I have a 20 Ampere connection and my friend has a 15 Ampere connection. An hour later I called again and a guy told me that the connection values are written on the meter 15/45 and that we both have a 15 Ampere connection. This connection can be used up to 45 Ampere.

In this regard a question - can anyone here explain to me why this is not called a 45 Ampere connection then?

But I begin to understand. The electrician that should install the water heater saw the 5/100 on the new electronic meter (there is no 15/45 anymore) and thought and said that the house connection is only 5 Ampere and so he refused to do the (free) installation. Or he was too lazy.

My friend has a townhouse with 3 floors and he also said that she should install a fuse box on every floor. I understand that this would be nice to have somehow but I also have the feeling that he wanted to extend the free installation to make some money. What do you think? I myself don't have a fuse box in every room of my condo... 

[bankruatsteve]

29 minutes ago, Oldie said:

In this regard a question - can anyone here explain to me why this is not called a 45 Ampere connection then?

TIT  A 15/45 is 15A nominal, 45A "max".  The cable size between the meter and the CU and grid capacity to supply will determine what the connection is capable of providing.

39 minutes ago, Oldie said:

said that the house connection is only 5 Ampere and so he refused to do the (free) installation. Or he was too lazy.

Yah, either uninformed or lazy.

[Oldie]

13 hours ago, Crossy said:

Yeah, the 5(100) electronic meters are "one size fits all" and maintain accuracy to (and beyond) 100A. The numbers really don't mean anything as to the supply "size" any more.

The mechanical meters are calibrated at the smaller number, the larger number being the maximum current.

The mechanical meters are incredibly robust and won't die even with a continuous 100% overload, they will however lose accuracy (bet they don't read low). 

Do you understand why they call it a 15 Ampere connection? It is good for 45 Ampere. Why are they talking about 15 Ampere then? 

[Crossy]

1 minute ago, Oldie said:

Do you understand why they call it a 15 Ampere connection? It is good for 45 Ampere. Why are they talking about 15 Ampere then? 

Nope. I would call it 45A too. TiT.

Many, if not most 15/45 meters have 63A incoming MCBs anyway.

 

[sometimewoodworker]

2 hours ago, Oldie said:

Do you understand why they call it a 15 Ampere connection? It is good for 45 Ampere. Why are they talking about 15 Ampere then? 

The answer is because that is how it is named, why it’s called that probably has a reason in the past, that your 15/45 meter will happy supply 80A all day long (if your cables are big enough and the supply strong enough) is irrelevant, but as @Crossy said you will be charged for more power than you actually use.

 

You could equally usefully ask why the speed limit is 56mph on main roads. The answer is, because it is.

[Oldie]

10 hours ago, sometimewoodworker said:

The answer is because that is how it is named, why it’s called that probably has a reason in the past, that your 15/45 meter will happy supply 80A all day long (if your cables are big enough and the supply strong enough) is irrelevant, but as @Crossy said you will be charged for more power than you actually use.

 

You could equally usefully ask why the speed limit is 56mph on main roads. The answer is, because it is.

Your explanation is a bit too simple. There is for sure a reason for the 15/45 and also for the new 5/100 on the electronic meters. And the 15/45 will not supply 80 Ampere all day long because the 63 Ampere breaker or the 50 Ampere breaker (at newer installations) will not allow this. And why should I be charged for more power than I actually use? 

[bankruatsteve]

7 minutes ago, Oldie said:

And why should I be charged for more power than I actually use? 

You don't seem to get the explanation that the meters are labeled as such for calibration.  IE: The meter should accurately measure energy usage within the calibration specification.  The breakers do control maximum usage but the meter has zero affect on supply or consumption.  It is just to measure.

[Oldie]

53 minutes ago, bankruatsteve said:

You don't seem to get the explanation that the meters are labeled as such for calibration.  IE: The meter should accurately measure energy usage within the calibration specification.  The breakers do control maximum usage but the meter has zero affect on supply or consumption.  It is just to measure.

I understand the calibration. His answer because it is like this was too simple. I always try to understand things. 

Here is a longer description of the PEA in English !!! and Thai. The link will download a pdf document written by the PEA. 

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjWi8W3zanvAhXNQ30KHZLSAfwQFjAKegQIDhAD&url=https%3A%2F%2Fwww.pea.co.th%2FWebapplications%2Ftor%2FAttachments%2F06f861ae-2c93-4462-b015-aaa5e9c97a9b%2F%E0%B8%81%E0%B8%9F%E0%B8%A0.%E0%B8%81%E0%B8%88%E0%B8%99.%E0%B8%9B(%E0%B8%A1)--004.2-2561.pdf&usg=AOvVaw0t1dzmvuyzbWHCizw4RlaN

[bankruatsteve]

That looks like an RFQ.  Anyway, most of us don't really know why the meters are defined like that (5/15, 15/45, 30/100).  It could be that it helps the PEA determine supply demand and phase balancing.  Again, the meter has zero control of supply or consumption.

[Oldie]

9 minutes ago, bankruatsteve said:

That looks like an RFQ.  Anyway, most of us don't really know why the meters are defined like that (5/15, 15/45, 30/100).  It could be that it helps the PEA determine supply demand and phase balancing.  Again, the meter has zero control of supply or consumption.

I know that the meter only measures. The PEA guy told me to look at the meter to find out the max power you can get with the connection. The new electronic meters with the rating 5/100 don't give you any indication anymore how much power you can use. I guess if you don't ask the PEA the best option is to look at the main fuse and hope that they installed the correct one. 

In respect of the new electronic meters. Does anyone know if they transmit the data automatically. Recently I saw a PEA guy standing in front of the here installed meters. He had a small printer and I couldn't see it clearly from the side but I think whenever he pressed the button on the meter the printer printed something. Do they still have to check the power consumption this way?

[maxpower]

3 hours ago, Oldie said:

There is for sure a reason for the 15/45 and also for the new 5/100 on the electronic meters.

Electricity meter 15/45 Class ? 

Ib 15A Imax 45A

Imax is the point up to where the meter should remain accurate.

Depending on class a percentage of value Ib will determine at what current the meter starts registering. Eg 40mA

[Oldie]

4 minutes ago, maxpower said:

Electricity meter 15/45 Class ? 

Ib 15A Imax 45A

Imax is the point up to where the meter should remain accurate.

Depending on class a percentage of value Ib will determine at what current the meter starts registering. Eg 40mA

I know. But do you understand why the max value is 3 times the base value? 5/15 and 15/45. I couldn't find an explanation. At 30/100 it is almost the same. And it still doesn't make any sense to me that they call it a 5 or 15 Ampere connection if it is good for much more. Perhaps it is really only TiT... 

[maxpower]

18 minutes ago, Oldie said:

I know. But do you understand why the max value is 3 times the base value? 5/15 and 15/45. I couldn't find an explanation. At 30/100 it is almost the same. And it still doesn't make any sense to me that they call it a 5 or 15 Ampere connection if it is good for much more. Perhaps it is really only TiT... 

I explained why they have these wide apart values on the meter. Depending on class, Ib determines at which point the meter starts registering.
This value will be much lower for a meter with a low Ib like 5/15.

Calling the connection 5/15 indicates the max accuracy point and value used to set start point (Is)

For electronic metering one size often fits all

 

Clue - Its advantageous to match the meter accuracy range with the users max demand.

Edited March 12, 2021 by maxpower

[sometimewoodworker]

On 3/12/2021 at 7:18 AM, Oldie said:

Your explanation is a bit too simple. There is for sure a reason for the 15/45 and also for the new 5/100 on the electronic meters. And the 15/45 will not supply 80 Ampere all day long because the 63 Ampere breaker or the 50 Ampere breaker (at newer installations) will not allow this.

Just because it’s simple doesn’t make it wrong. 
 

You have already been given the reason for the numbers on the meters, test range.

Yes the 15/45 will supply 80A all day long. Look at what you have written, it is not the meter that is the limit in your scenario, but your choice after the meter.

FWIW your 63A breaker is unlikely to trip with a sustained 70A load for a long time, but that is not relevant to the fact that your 15/45 meter will supply 80A 24/7 (assuming the PEA supply is capable) 

Quote

And why should I be charged for more power than I actually use? 

Apart from starting a sentence with a conjunction, though the PEA probably won’t charge extra for that  ????, if your usage is outside the test range it is likely that the meter will not be accurate and extremely likely that it is not going to read on the low side.

Just to add fuel to the fire. There is also the likelihood that at sometime in the future, with the advent of technology in meters you will stop being charged for real power and start being charged for apparent power, so all the wonderful LEDs that have power factors in low decimals will suddenly be costing you anything from double to 9 times the real power usage, won’t that be fun?

[Reigntax]

Can someone please confirm that these charges are fines for illegal modification to supply meters?

or are they installation

meter costs?

[sometimewoodworker]

1 hour ago, Reigntax said:

Can someone please confirm that these charges are fines for illegal modification to supply meters?

Yes they are.