Utility CT metering of solar?

tortuga

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Question for you utility folks, and possibly solar folks,
Is there anything special to net metering commercial solar? Are the actual CT's different size or type?
Are the meter jaws different? Anything ?
I was asked look into this for a church.
They have a proposed roof top solar project lined up 30kVA, and there is a July deadline now.
they have what appears to be an existing service of 400-500A at 208V 3ph,
pole bank of three cans then service is underground from pole.
Switch gear in in church basement has 5 main breakers and a CT metering section below, probably 1970's era.
This particular utility is very large possibly thru mergers and buy outs and has massive territory in several states they appear to have a unified standard for CT metering, that this churches CT meter setup does not meet, but it did meet at one time.

There was no issue with the Church and the utility prior to the request for solar net metering, and since the Church's demand usage is very low the utility does not need to upgrade a transformer or do anything other than install a NET meter.
The utility wants the CT's brought up to current standard, which involves moving the location of the Meter, and since the CT's have to be close to the meter (like within a foot) its no small task and the cost will kill the project.
I have ran into this beofre when CT's were on a pole and the utility did not want metering on their pole, but I am curious if there is a technical or life safety reason to upgrade the CT's or is this just red tape?
thanks
 
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There is always a chance in any solar project that an AJH will require that something else be brought up to the current codes or standards. That's what the utility is doing here. You can try to talk them out of it but if they require it for the solar install then you have to give it to them. Utility standards change over time and they will take the opportunity to get a customer to update to the current standard.
 
pv_n00b said:
There is always a chance in any solar project that an AJH will require that something else be brought up to the current codes or standards.
Click to expand...
AKA "you touch it, you fix it". Here in Austin there are a lot of residences and some commercial buildings that were constructed before an external service disconnect was required by the city code; adding a PV system will trigger a requirement to upgrade the service to present code even when the solar is to be added on the load side of the service OCPD.
 
Thanks for the replies!
The issue at hand here is the Oreogn rules, the 'meter' while located outdoors is basically in a little courtyard with no exterior accesses and there is a requirement for a PV disconnect switch that must be 'readily accessible' to the public utility 'at all times' and located within 10 feet of the public utility’s meter.
They want the PV disconnect on the front of the building, so they are requiring the 'meter' to move, but their 'meter' cant be more than a few feet from the CT can that effective means the service has to move.
I was able to get a a reference to the Oregon Administrative Rule (OAR) 860-039-0015:
(2) Except for customer-generators established as net metering customers prior to the effective date of this rule, a customer-generator of a public utility must install and maintain a manual disconnect switch that will disconnect the net metering facility from the public utility’s system. The disconnect switch must be a lockable, load-break switch that plainly indicates whether it is in the open or closed position. The disconnect switch must be readily accessible to the public utility at all times and located within 10 feet of the public utility’s meter.
Then there is a section (b)
(b) The disconnect switch may be located more than 10 feet from the public utility meter if permanent instructions are posted at the meter indicating the precise location of the disconnect switch. The public utility must approve the location of the disconnect switch prior to the installation of the net metering facility.
So perhaps I'll try for that wish me luck!
 
Why do you put "meter" in quotes? If the POCO's metering equipment is not up to present code the AHJ might require you to bring it up irrespective of the location of the PV AC disconnect.
 
ggunn said:
Why do you put "meter" in quotes?
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Thanks yeah i put that in quotes because the POCO had approved the net-metering with the condition of moving the 'meter' so its within 10 feet of the PV AC disconnect, and the chosen location was about 50 feet away from the CT can, so Church was given the impression that moving the 'meter' meant just move the little meterbase not the entire CT cabinet which is part of the switchgear, and thus move the service. I spotted this discrepancy on the plans as I know the utility requires the meter to be within a few feet of the CT can.
 
tortuga said:
Thanks yeah i put that in quotes because the POCO had approved the net-metering with the condition of moving the 'meter' so its within 10 feet of the PV AC disconnect, and the chosen location was about 50 feet away from the CT can, so Church was given the impression that moving the 'meter' meant just move the little meterbase not the entire CT cabinet which is part of the switchgear, and thus move the service. I spotted this discrepancy on the plans as I know the utility requires the meter to be within a few feet of the CT can.
Click to expand...
Yes, a POCO meter must include its CT enclosure.
 
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