Let me see if I have your structure wiring correct:
- Your main service panel (the one where the power comes in from the utility) has a 30A, non-GFCI breaker.
- You had a sub-panel added in your brewing area that contains a 30A, GFCI breaker.
- The wiring from your main panel to your sub-panel is 4-wire, fed from the 30A breaker in the main panel.
- Neutral and ground are bonded (connected) together in your main panel.
- Neutral and ground are isolated from each other in your sub-panel.
- There is a 4-wire cable from your sub-panel to your 4-slot outlet.
Is all of the above correct? Is your sub-panel in a separate building from the main panel?
Note: I think I was confused earlier, and thought your first panel was plugged into a 3-slot outlet.
Brew on