Line Side Tap - With A CT utility meter

[Anode]

When installing a PV system via a line side tap, in a configuration where there is a CT utility meter, how have any of you in the past gone about making sure the solar production also gets metered?

I guess it would depend on where you tap the feeders with the ac output feeders, and where the utility meter CT's are measuring, and ideally wanting to be between those two points?

But could you instead add CT's to the solar feeders, and connect them to the utility meter somehow... If there was that situation where you could not tap between where the utility Ct's are measuring the feeders, and the main disconnect?

Curious...

 

[ggunn]

When installing a PV system via a line side tap, in a configuration where there is a CT utility meter, how have any of you in the past gone about making sure the solar production also gets metered?

I guess it would depend on where you tap the feeders with the ac output feeders, and where the utility meter CT's are measuring, and ideally wanting to be between those two points?

But could you instead add CT's to the solar feeders, and connect them to the utility meter somehow... If there was that situation where you could not tap between where the utility Ct's are measuring the feeders, and the main disconnect?

Curious...

Maybe I am misunderstanding the question, but the systems I have designed have almost all had their own dedicated revenue grade meter irrespective of whether they are line or load side interconnected. Whether your tap point is inside or outside the utility meter would depend on whether the system is to operate under a feed in tariff (FIT) or not. The utility is most likely not going to want you to mess with their metering.

 

[iwire]

When installing a PV system via a line side tap, in a configuration where there is a CT utility meter, how have any of you in the past gone about making sure the solar production also gets metered?

The one time I was involved in something like this the customer had to pay the power company to relocate the CT metering up stream inside the pad mount transformer.

It was my job to remove the old CTs inside the building and replace them with copper bus bars.

 

[jaggedben]

I'm going to assume this is net metering and the connection has to be on the load side of the existing meter...

It's really no different than any other supply-side connection. You need a spot to connect between the meter (CTs in this case) and the existing service disconnecting means. (It's not so much 'ideal' as absolutely necessary). If you can't do that in a code compliant manner, then you either need to go for some other connection option, or move the metering in cooperation with the utility, as in the scenario iwire described.

I suppose you could propose to the utility that they meter the solar separately but most likely the laws and regulations will make that not a real option. They would probably tell you that has to be a separate meter, and then your net-metering arrangement probably won't be valid.

If you try to mess with a utility's CT setup without telling them that will surely get you in plenty of trouble.

 

[Anode]

I'm going to assume this is net metering and the connection has to be on the load side of the existing meter...

It's really no different than any other supply-side connection. You need a spot to connect between the meter (CTs in this case) and the existing service disconnecting means. (It's not so much 'ideal' as absolutely necessary). If you can't do that in a code compliant manner, then you either need to go for some other connection option, or move the metering in cooperation with the utility, as in the scenario iwire described.

I suppose you could propose to the utility that they meter the solar separately but most likely the laws and regulations will make that not a real option. They would probably tell you that has to be a separate meter, and then your net-metering arrangement probably won't be valid.

If you try to mess with a utility's CT setup without telling them that will surely get you in plenty of trouble.

Yes, it is for net metering. I do realize these were my two options here. It is well in advance of actually proposing anything, so I appreciate the input. You all are an invaluable resource.

We will be tapping between the CT's and the switchgear, the question was more hypothetical..