Running PV wires in an attic/indoors/basement guidelines?

[pvgirl]

Oddly some Victron charge controllers are listed to UL standards: https://www.victronenergy.com/uploa...-1S-SmartSolar-MPPTs-150-45-up-to-250-100.pdf

How these got listed without the ability to use NEC compliant wiring method I don't know.

 

[zanydroid]

However, the NEC code states metal conduit to disconnect, I don't recall if it needs to be in metal conduit after the disconnect.

2017 vs 2020 difference as covered a few times above

 

[zanydroid]

Oddly some Victron charge controllers are listed to UL standards: https://www.victronenergy.com/uploa...-1S-SmartSolar-MPPTs-150-45-up-to-250-100.pdf

How these got listed without the ability to use NEC compliant wiring method I don't know.

Maybe expect you to install in a cabinet or enclosure (can’t imagine US installers being happy with this extra bother, so if this is the case I’ll confirmation bias into this being another example of Victron not caring about the U.S.).

Or the UL version has a custom wire area (the MultiPlus UL has that change, though I think it also was conduit compatible already).

 

[Quattrohead]

Batteries cables should be contained within metal conduit too.

 

[cs1234]

At what point does a large metal box become a room, and then you have to use conduit again? In other words, when is a raceway, no longer a raceway, but a room?

 

[pvgirl]

At what point does a large metal box become a room, and then you have to use conduit again? In other words, when is a raceway, no longer a raceway, but a room?

depends if it's listed....

 

[Plum Crazy Rob]

I'm not sure if UL1741 covers arc fault, and ground fault for solar. But if it had listed arc fault it would also be listed for UL1699 which is the standard for pv arc fault, which this unit doesn't seem to be to listed to. Also on page 24 on the manual seems indicate that ground fault protection must be provided, but not that it is not inincluded.

Hey!...dredging this up to make sure everyone knows YOU can register a free account at UL.com then select the DIGITAL VIEW option to read and under US Fair-Use Copyright doctrine quote YOUR favorite UL docs for free. Try it, you'll like it! Works best on laptop/desktop.

Re ground fault UL 1741 sez:
34 DC Ground Fault Detector/lnterrupter
34.1 Inverters or charge controllers with direct photovoltaic inputs from a grounded photovoltaic array or
arrays shall be provided with a ground-fault detector/interrupter (GFDI). The GFDI shall be capable of
detecting a ground fault, providing an indication of the fault, interrupting the flow of fault current, and either
isolating the faulted array section or disabling the inverter to cease the export of power. The GFDI shall
comply with 34.2 -34.6 and Sections 56
Exception No. 1: AC modules are not required to be provided with a GFDI.
Exception No. 2. Inverters or charge controllers without GFDI devices may be used when the unit includes
markings in accordance with 69.4(S)

(69.4(S) says manual must say GFCI/GFDI not provided, consistent with PVgirl's findings), otherwise GFCI MUST BE provided per UL1741..

And re arc fault UL1741 has:
34A PV DC Arc-Fault Protection
34A.1 Equipment that includes PV DC arc-fault protection functionality shall comply with the applicable portions of the Standard for Photovoltaic (PV) DC Arc-Fault Circuit Protection, UL 1699B. PVRSS, PVRSE, PVIE and other electronics that are connected within PV array strings, shall be present in a
normal operating condition during evaluation according to applicable UL 1699B requirements and tests
including, but not limited to, those defined for PV AFCI for use with PV DC to DC converters
34A.2 Equipment and systems such as, but not limited to, PVRSE, PVRSS, and PVIE that have components such as, but not limited to, power supplies and capacitors integrated or connected to PV system dc circuits, which are required to have PV DC arc-fault protection shall be evaluated and shall not
interfere with the PV DC arc-fault protection functionality. Interference includes filtering, masking, and attenuation of arc signals:
Note: Switching noise and input filter capacitance from such equipment and systems integrated or connected to PV
system DC circuits can interfere with the PV DC arc-fault protection functionality . Electromagnetic compatibility testing is outside the scope of this
standard. However, manufacturers should ensure that such eauipment and systems will not interfere with the PV DC arc-fault
Protection functionality. Both of the following should be considered:

A) Evaluate the conducted emissions from such equipment and systems back to PV system DC circuits using the test
CISPR 11:2015 for DC ports from 9khz to
50khz. Since CISPR 11 does not have limits for this frequency range, evaluate the PV system DC circuits with and without such equipment and systems to determine their noise
contribution. This noise contribution, especially broadband noise and switching noise should not interfere with the PV DC
arc fault protection functionality. The test procedure and noise levels are part of a proposal which is being worked on and will be proposed in the future.

B) Evaluate the suitability of the input impedance of such equipment and systems using the Standard for Photovoltaic (PV) DC Arc-Fault Circut Protection, UL 1699B to verify the input filter design does not
interfere with the PV DC arc fault protection functionality.

Again more or less consistent that if a UL1741 compliant inverter has AFCI it must comply with, and presumably would list UL1699B on its label / paperwork. AFCI not required as PART OF UL1741...

 

[Plum Crazy Rob]

Bottom line re the EG4 mini split doesn't this say for NEC2020 or NEC2023 DC PV compliance on or in an occupied structure, you'll need to wait until it includes built in DC AFCI or someone devises a standalone?