3 phase meter experts please: How to choose whether CT connection is needed?

FAI

I am working on a new build which is at first fix stage.
The site has a 3 phase supply which is currently feeding a 3 phase meter set up for temporary commercial use for the temporary accomodation and building requirements.
I have a contract with SSE (I live near Reading, Berks) to re-route the 3 phase supply to the new property. They have provided a me with a new MPAN.
On Nov 22nd I move to Scottish Power onto their Fixed Price Nov 2014 tariff, and subesquently plan to move onto the E7 version of that tariff when the new meter is installed.

I have help on this board from Terrylw1 who is checking which 3 phase meters are suitable (in this area).

Here is a description of the Domestic supply:
3 phase, 400 volts, alternating current, at 50Hz, terminating in a fused cut out with a maximum capacity of 100 Amperes subject to an after diversity of demand for 35kVA for the entire development.

The current 3 phase meter is set up with 3 off 100A fuses.

Please could you help me by explaining the difference between a CT connection and a whole current connection, and which I should go for?

JC_Derby

Whole current metering - like your house meter, it measures the whole of the current running through the cable.
CT metering CT means current transformer. Coils will be fitted round the incoming cable phases ie 200/5.
What you need to tell us is what size of service you are after. anymore than 69kva and you will be (most probably) told that you need to have CT metering.
. I also believe they are billed differently, ie CT metering is possibly more expensive than whole current (but i dont know).
As for which you should go for, i dont think you will have a choice, as ive said it will be down to the size of supply you require.

JC_Derby

just re read your post, if the supply size stays the same...ie at 3 phases with 100amp fuses, that will be whole current metering.

FAI

JC_Derby wrote: »

just re read your post, if the supply size stays the same...ie at 3 phases with 100amp fuses, that will be whole current metering.

Many thanks:)
It is good to understand it all, and good to know the answer too.

FAI

Terrylw1

JC_Derby wrote: »

just re read your post, if the supply size stays the same...ie at 3 phases with 100amp fuses, that will be whole current metering.

Cheers JC_Derby, I mentioned to FAI that a thread specifically aimed at the supply/meter might get the attention of one of you techie guys.