Jason:
Several issues come to mind: 1. I think the question that dictates is the insulation rating of the Envoy and associated wiring as possibly exposed to voltages within the panelboard. This is akin, but not identical, to the scenario described in NEC 300.3(C). Insulation rating matters if any low voltage equipment could in any odd-ball scenario contact an energized part. I don’t imagine the Envoy assembly has an insulation rating. The insulation rating must also apply to any communications, CT or any other purposed conductors associated the Envoy. Indeed, this is the same problem regularly encountered when installing energy monitor equipment, such as E-gauge or similar, in panels. 2. If there are any power line communications interference problems, you want your Enphase branch circuits to land in a separate sub-panel so you can apply filtering if needed. The Envoy must be connected to that sub-panel. Enphase makes some custom combiners for this specific purpose. Any reason you are not using a sub-panel or Enphase combiner to collect Enphase circuits? 3. If the Envoy is in a metal can will the Wi-Fi work? 4. If there is so much room, would you consider mounting an enclosure in the panel inside of which the Envoy could be mounted? A PVC pull box, as one option, would not diminish the Wi-Fi signal any more than it already is and would provide the insulation needed to keep energized parts away from the low voltage equipment that is the Envoy. I have even bent up some galvanized sheet metal partitions to install in breaker panels. If well fabricated and bonded, this has made me feel warm and fuzzy about the safety of same. 5. Based on the above, I would not put a naked Envoy in a breaker panel unless it was my own house. I hope these musings help you decide on a design strategy that you and the AHJ think is safe and legal. Sincerely, William Miller Miller Solar 17395 Oak Road, Atascadero, CA 93422 805-438-5600 www.millersolar.com CA Lic. 773985 *From:* RE-wrenches [mailto:[email protected]] *On Behalf Of *Jason Szumlanski *Sent:* Thursday, October 1, 2020 2:00 PM *To:* RE-wrenches *Subject:* [RE-wrenches] Enphase Envoy Enclosures Can anyone point to any code issues with mounting an Envoy inside of a panelboard? For example, when installing a 3-phase commercial system with a large 400A AC combiner panelboard, there is often PLENTY of room to mount an Envoy inside on a DIN rail. Aside from the manufacturer's instructions not specifically listing this option, I can't see any reason that it would be prohibited. The only downside I can see would be slightly more difficult access to service buttons. I would argue that it is better. The DIN rail would be bonded to the enclosure. The DIN rail that Enphase ships with the Envoy is too short to accept a DIN mounted grounding terminal. When mounting in a non-metallic enclosure I run an EGC to a grounding terminal on a longer DIN rail that I install, not the included one. I'm wondering how people handle the lack of a ground terminal on the Envoy and whether they even run an EGC along with the circuit conductors when mounting an Envoy in a non-metallic enclosure. I have not been able to get a good answer from Enphase on how they expect this to be accomplished. I suppose if the Envoy does not need an equipment ground because it is insulated, and the DIN rail is not exposed once the Envoy is mounted. Maybe it is their opinion that no EGC is required, but I see the DIN rail as needing an EGC. Anyway, that's a lengthy side note. I'm mainly wondering if the Envoy can be mounted in a panelboard. Jason Szumlanski
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