Ground Fault Interrupter (GFI)
A GFI is not to be confused with a circuit breaker found in your electrical breaker panel. Regular breakers are rated for specific current ratings and will switch off (or 'trip') if ever the rated current is exceeded on the circuit they control. The sole purpose of breakers is to protect the wires from overheating.
A GFI (or more accurately, a residual-current device) on the other hand is not used to protect wires or devices - it protects the equipment operator. A GFI will cut power when it detects that the current going in to a circuit does not match the current coming out of the circuit. Often this imbalance (typically only a few milliamps) is caused by current leakage through the body of a person who is grounded and is accidentally touching an energized part of the circuit.
The distinction is important: A circuit breaker saves equipment, a GFI saves lives. While the electrical code varies from country to country, in North America GFIs are typically required in kitchens, bathrooms, and other places that can be wet. A GFI should most definitely be used in the circuit that powers your brewery control panel.
This GFI can be installed in one of two places: Either in the double-pole 30 amp circuit breaker in the electrical panel, or in-line with the control panel power cord.
We managed to find a 240V AC 30 amp GFI cord that was previously used to power Xerox copy machines for less than a double-pole 30 amp GFI breaker. These special 30A GFI power cords unfortunately are very difficult to find so most users will be required to install a double-pole 30A GFI breaker in their electrical panel.
Approximately half a dozen different electrical panel brands exist (Cutler Hammer, Seimens, GE, etc.) so if you purchase a double-pole 30A GFI breaker make sure that it matches your electrical panel. Refer to a qualified electrician for assistance if required.
Please do not forgo using a GFI thinking that simply being 'careful' will be enough. Like the seat belts in your car, a GFI exists because accidents or failures happen, even on properly designed, built, and operated equipment.