'66,

I think We had this conversation before somewhere. Don would know the particulars. I just remember having the same thought about what to do with the Neutral and that it is covered in the Instructions.

I've seen 2 types of Disconnect/with GFCI. One is really nothing more than a Sub panel with a GFCI Breaker in it. I've seen it come as a package in 40, 50, and 60 amp models.

The other is a pullout with a BlankFace (120v) GFCI which monitors all 3 conductors and controls the coil for the Load Contactor. Because the GFCI is 120v it needs at least a #12 neutral even if the Load doesn't need it. See Illustration Below:

[Linked Image]

Spec sheet:
https://www.electrical-contractor.net/theory/240vGFCI-Relay.pdf

Bill

Bill