Communications Equipment for Photovoltaic equipment tap at equipment location

[TimLathen]

We have a project in California that is a roof top installation with the inverters connected line-side in accordance with NEC 705.12 (A).
We have a SolarEdge Commercial Gateway / Data Logger, with a set of environmental sensors the sensor wires are limited by length and shorter is better as they are sending a voltage or current to the gateway and not a digital signal. The question I have is it ok to tap the solar photovoltaic line say a phase to neutral with an inline breaker feeding the gateway as it is part of the photovoltaic systems communication equipment?

 

[tortuga]

By 'solar photovoltaic line' do you mean:

Photovoltaic Output Circuit. (DC Circuit conductors between the
PV source circuit(s) and the inverter or dc utilization equipment)

or

Interactive Inverter Output Circuit. (AC conductors between
the interactive inverter and the service equipment or another
electric power production source, such as a utility, for electrical
production and distribution network.)

 

[TimLathen]

The AC side between the Grid-Tied inverter and the service equipment

 

[tortuga]

NEC defines that as the "Interactive Inverter Output Circuit." in article 705.
Since the output circuit is the conductors between the PV power supply
source and the final branch-circuit overcurrent device, i'd say that meets the article 100 definition of a feeder.
per 90.3 articles 705 or 690 would have to modify the rules disallowing a feeder tap.
I dont see anything in there preventing you from using one of the feeder tap rules in 240.21(B)
Others might chime in here.
Cheers
Edit sorry I missed the line side tap!
Thats tapping a tap you can't do that.
You could possibly tap the DC side and use some kind of DC/DC converter / regulator.

 

[TimLathen]

NEC defines that as the "Interactive Inverter Output Circuit." in article 705.
Since the output circuit is the conductors between the PV power supply
source and the final branch-circuit overcurrent device, i'd say that meets the article 100 definition of a feeder.
per 90.3 articles 705 or 690 would have to modify the rules disallowing a feeder tap.
I dont see anything in there preventing you from using one of the feeder tap rules in 240.21(B)
Others might chime in here.
Cheers
Edit sorry I missed the line side tap!
Thats tapping a tap you can't do that.
You could possibly tap the DC side and use some kind of DC/DC converter / regulator.

 

[TimLathen]

“705.12(A) Supply Side. An electric power production source shall be permitted to be connected to the supply side of the service disconnecting means as permitted in 230.82(6). The sum of the ratings of all overcurrent devices connected to power production sources shall not exceed the rating of the service.”

 

[TimLathen]

My question is is this is the control circuit

“705.12(A) Supply Side. An electric power production source shall be permitted to be connected to the supply side of the service disconnecting means as permitted in 230.82(6). The sum of the ratings of all overcurrent devices connected to power production sources shall not exceed the rating of the service.”

for the equipment Is the parasitic load allowed.

 

[TimLathen]

The question is would this parasitic load directly related to the equipment as a control circuit for the equipment, be considered part of the photovoltaic system and thus allowed?

 

[tortuga]

The question is would this parasitic load directly related to the equipment as a control circuit for the equipment, be considered part of the photovoltaic system and thus allowed?

Your 705.12(A)tap terminates on an OCPD for the inverter, you can tap the load side of that OCPD, but not the tap it self.

 

[jaggedben]

I think that we may need to see a line diagram.

If you have a single inverter branch circuit I would say you cannot tap that. Violation of the dedicated overcurrent and disconnect rule in 705.12.

If you have multiple inverters combined in a panelboard with an overcurrent device upstream, then you have a feeder in between that is just fine to tap.