meter change

[Steve]

When changing the meter on a polyphase CT type cutout, is it nessecary to turn off the electricity? Perhaps Roo could advise? I wouldn't think it was nessecary, as the electricity doesn't go through the meter itself, but apparently the voltage on the CT wires can get very high?

(Someone is coming to change our shop's meter next week and i'd like to know if we'll need to close the shop!) They are fitting a "smart meter" whatever that is????

 

[cheesepuff]

the only person fitting a meter should be the DNO. they will turn off the electrictythe correct way and fit it. Why should you need to know? also I think a smart meter is a digital one?

 

[Adam_151]

apparently the voltage on the CT wires can get very high?

If the secondary side of the CT is left open circuit, you'll get high voltages across the secondary, shorting links have to be fitted if the secondary circuit needs to be disconnected while the primary is still live

As to what the DNO actually do, I don't know

 

[Steve]

the only person fitting a meter should be the DNO. they will turn off the electrictythe correct way and fit it. Why should you need to know? also I think a smart meter is a digital one?

I know. They are doing it.

Because I shall be working and I want to know if they will need to turn the power off. All I've got is "they may need to turn the power off". The current meter is already a digital one. Its white, rounded bottom, 2 line LCD, yellow display button. Less than 5 years old in fact.

 

[ricicle]

apparently the voltage on the CT wires can get very high?

If the secondary side of the CT is left open circuit, you'll get high voltages across the secondary, shorting links have to be fitted if the secondary circuit needs to be disconnected while the primary is still live

Although the voltage should not rise in the secondary circuit of the CT if the supply is completely isolated and no current can flow in the primary

 

[Deleted member 54734]

Sorry can't help.

I know nothing about CT metering.

In our company we have a specialist team of around 8 fella's that do CT.

AFAIK all are sparks, all are on the next wage band up from me and they deal with just CT equipment.

Sounds like you've got an ABB polyphase meter and if it's only 5 yrs old your DNO must be in the middle of some kind of scheme with these so called smart meters what ever they are?

They probably will turn you off but can't say for sure as I don't know whats involved.

Just be prepared to be turned off just in case.

 

[Steve]

Sounds like you've got an ABB polyphase meter and if it's only 5 yrs old your DNO must be in the middle of some kind of scheme with these so called smart meters what ever they are?

Yes its an ABB.

And its not the DNO, its our company being awkward and wanting to know exactly how much energy every store is using so they can break it down daily. I assume these smart meters transmit data to our head office or their head office somehow.

Ooh heres a photo of it . . .

 

[Deleted member 54734]

Ah....
I see, a meter to provide all the service's of... er well the meter you already have???

PMSL

Unless it does transmit your your head office that is.

 

[Steve]

I know. madness.

Our company introduced monthly meter readings last year, but it hasn't been overly successful. I think they also want to eradicate people taking wrong readings. For example, some older meters have a red LED display, which cycle through the date, time, max dem etc. Unfortunately it is unclear on most of these meters what reading is what, and I have known certain managers send the readings including the date, time, max dem, 1, 2, 3, god knows what our head office were charging them for electricity If the smart meter does send daily readings, they will be able to break down the stores into efficient and inefficient bands, and generally sharpen up on accuracy too. And detect sharp jumps in consumption too.

 

[plugwash]

also they may be able to get a better average price out of thier suppliers if thier suppliers know what times they are using the power and/or they move the times of max consumption to times that are slack for the supplier.

 

[efiste2]

Done many polyphase meter panel changes ,whilst the consumer stayed on supply, Basically we removed the meter's voltage supply fuses (usually at cutout) and also shorted the CT's out with a clip short. (making the meter onake dead) Although this was some time ago , the meter tech has changed, but the principle is more or less the same.................just to confirm the warning already posted, DO NOT LEAVE A CT (current transformer) OPEN CIRCUIT.

 

[Steve]

Well they have changed the meter! The new one is almost exactly the same as the old one, but for a little black wire and an antenna!

The big silver circle and the hole in the middle - what is the purpose of this?

"Multi-utility compatible" ¿Que?

What does "total import KWh" mean?

Apparently there are at least 600 of our stores having these meters fitted.

Thx

 

[JohnD]

that's a plunger on top, for the demolition of your shop.

 

[Steve]

that's a plunger on top, for the demolition of your shop.

hehe, it does rather looks like that doesn't it!

And why would they want to demolish my shop?

 

[efiste2]

Not too well up on these new fangled things, but obviousley thats a data transmission aerial, so they can read your meter remotely, the circle thing "it used to be anyway" is used for programming the meter with tarriffs ct ratios etc etc , and total import Kwh is the number of KW Hours the shop has used. Not sure what multi utility compatible means, ROO is the metering man, he will know!!
I think pressing thast yellow button will scroll the digital display through all the readings that the meter records. including time,date,max demand etc etc,