Entrance wiring

[hornetd]

Good question. The CAFI detects and reports (via its internal diagnostics) 6 different faults, including ground faults:
View attachment 21976
...but its function as a GFCI is questionable, and generally not explicitly mentioned in Schneider's literature. In fact, I was told by a Schneider tech support guy that it was NOT a GFCI. They say: "Breakers designed to protect against parallel and series arcs are called Combination Arc-Fault Circuit Breakers, have a CAFI suffix, and have a white test button. An example catalog number is QO120CAFI." I remain puzzled, but will continue digging in to it as time permits. Somewhere I found a pretty good internal diagram of how a GFCI works, but it's escaped me for now.

At least some of the CAFIs have a Ground Fault Interrupter (GFI) function that uses ground fault detection to protect against arcing to ground. But unlike a Ground Fault Circuit Interrupter (GFCI) the GFI trip level is 30 mA. Until rather recently GFI protection of equipment was only available for rather large current circuits. The National Electric Code (NEC) of the United States only required GFI protection of Wye connected Services over 800 Amperes.

 

[Humbleabode]

Hi Tom - here is what I came up with for my entrance setup. If you wouldn’t mind taking a look and giving me any feedback I’d appreciate it!

 

[hornetd]

Is the service equipment enclosure in your second photograph <https://www.houserepairtalk.com/attachments/ea47d648-6686-44bb-aab5-f4f7918d2e00-jpeg.22049/> indoors or outside? Would you please post a photograph of the bottom side of the enclosure cabinet with the metal of the wall of the cabinet dead center of the photograph so that I can see both the inside and outside of that edge of the box in the same frame. If that is difficult to do then post two photographs; one looking slightly upwards at that cable entry, and one looking slightly downward at the same cable entry. I cannot tell if a connecter of Duct Sealant was used their. The use of Duct Sealant alone on any cable entry is no longer compliant with the US National Electric Code (NEC). Everyplace that the Service Entry Cable (SEC) enters an enclosure there must be a suitable Connector used which is listed for use with type SE cable. Outdoor entries on the top and sides of an outdoor enclosure like the one on your Service Equipment Enclosure and your meter enclosure must use a weather proof connector were the connector squeezes a neoprene gland around the cable. That requires the installation of a threaded hub that provides the threaded opening for the connector. The crew from the electrical utility may add Duct Seal out of pure habit but it is the water proof SE cable connector which the NEC now requires. Most AHJs will allow the non waterproof SE connectors which look like an oversized NMC ["Romex"] Connector.

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Tom Horne