10 foot RSS exception

[Zee]

Does the exception still exist in NEC 2017 for inverter within 10 feet of array not needing rapid shutdown at all?

 

[PWDickerson]

No. The 2017 NEC essentially requires optimizers or micro inverters for all PV system on or in buildings.

 

[BBEE]

Take a look at 690.12, it's requiring module level shut down for roof mounted systems.

We've had to switch to using either Tigo or Solaredge on commercial projects.

Sent from my Pixel 2 using Tapatalk

 

[Carultch]

Does the exception still exist in NEC 2017 for inverter within 10 feet of array not needing rapid shutdown at all?

It never was an exception in the first place. It was a method of complying with the 2014 version of the rule. The rapid shutdown doesn't cease to exist, you just wouldn't need rapid shutdown specific equipment to comply (like a contactor or shunt trip combiner at the time). The rapid shutdown rule would only cease to exist, if your system never touched a building.

The working principles behind a inverter operation, would allow the entire the entire AC side to de-energize upon opening the master switch, and therefore the DC side that remained energized would have to remain within the array + 10 ft offset. The current rule in NEC2017 and NEC2020 no longer allows "combiner level shutdown"/"inverter level shutdown" like this. It tightens the boundary to a 1 ft offset, outside which 30V is the maximum, and requires max 80V within the array. Practically, this means module-level shutdown, since a typical module in open circuit is between 40 and 80V. With most modules, the most you could combine prior to a rapid shutdown device is parallel combinations of individual modules, since 2 in series usually exceeds 80V.