Relocate Current Sensors

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jaggedben said:
? I think you not seeing what's there. Those are current transformers (CTs).
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The device with the red wire (looks like it might be #6 AWG or #4 AWG) tapped onto the main feeder, is an insulation piercing connector. There is an equivalent on the other line, with a black conductor tapped. The tapped circuit that taps from the insulation piercers, leads to an LFNC conduit on the bottom right (looks like it might be size 1").
 
Carultch said:
The device with the red wire (looks like it might be #6 AWG or #4 AWG) tapped onto the main feeder, is an insulation piercing connector. There is an equivalent on the other line, with a black conductor tapped. The tapped circuit that taps from the insulation piercers, leads to an LFNC conduit on the bottom right (looks like it might be size 1").
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You are right and I missed it. Apologies to ceb58.

That said, while I don't prefer those particular connectors, there's nothing wrong with them in theory, or any reason that a backfed breaker must be used instead, if that is the tap for the solar. It allows them to use the 'opposite end' rule with the feed through lugs. There are parts of 705 to comply with, to be sure, but they may have done that.
 
jaggedben said:
You are right and I missed it. Apologies to ceb58.

That said, while I don't prefer those particular connectors, there's nothing wrong with them in theory, or any reason that a backfed breaker must be used instead, if that is the tap for the solar. It allows them to use the 'opposite end' rule with the feed through lugs. There are parts of 705 to comply with, to be sure, but they may have done that.
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If it is like most installs there in a sub panel down stream of the load side tap. By connecting an inverter with a max output current of 40A using a load tap at the feed through conductors of a meter-main panel with a 200A main breaker exposes the wire and equipment downstream of that conductor to 200A + 40A = 240A. This causes a potential overload of the connected 200A panel. 705.12(B)(2)(1), 705.12(B)(2)(2) The only thing that would make it ok is if the sub panel has a main breaker in it per 705.12(B)(2)(1)(b). Not to mention that the feeder wire in now only good for 180 amps due to the feeder not carrying the full load as described in 310.15 (B)(7)
 
ceb58 said:
Not to mention that the feeder wire in now only good for 180 amps due to the feeder not carrying the full load as described in 310.15 (B)(7)
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Except that if it's a 200A residential service, subsection (3) of the above says that any 200A feeder can be sized like it carries the full load, so there is no change in the feeder rating.

Cheers, Wayne
 
ceb58 said:
If it is like most installs there in a sub panel down stream of the load side tap. By connecting an inverter with a max output current of 40A using a load tap at the feed through conductors of a meter-main panel with a 200A main breaker exposes the wire and equipment downstream of that conductor to 200A + 40A = 240A. This causes a potential overload of the connected 200A panel. 705.12(B)(2)(1), 705.12(B)(2)(2) The only thing that would make it ok is if the sub panel has a main breaker in it per 705.12(B)(2)(1)(b).
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In other words, tapping the feeder is a legit method when done right. In this case, it allows them to connect at the opposite end of the main panel as well, which may avoid downsizing the main breaker below what the home requires.

ceb58 said:
Not to mention that the feeder wire in now only good for 180 amps due to the feeder not carrying the full load as described in 310.15 (B)(7)
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In addition to what Wayne pointed out, an intermittent interactive inverter should never be considered to decrease the load carried by a feeder. The feeder will likely still get asked to carry the full load. Nobody ever intended interactive sources to figure into 310.15(B)(7), and it shouldn't be read that way.
 
ceb58 said:
If it is like most installs there in a sub panel down stream of the load side tap. By connecting an inverter with a max output current of 40A using a load tap at the feed through conductors of a meter-main panel with a 200A main breaker exposes the wire and equipment downstream of that conductor to 200A + 40A = 240A. This causes a potential overload of the connected 200A panel. 705.12(B)(2)(1), 705.12(B)(2)(2) The only thing that would make it ok is if the sub panel has a main breaker in it per 705.12(B)(2)(1)(b). Not to mention that the feeder wire in now only good for 180 amps due to the feeder not carrying the full load as described in 310.15 (B)(7)
Click to expand...
Checked with the customer and determined that the sub panel does have a 200amp main.

Thanks for the info...
 
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