Have you tried using a plain 15/20 amp receptacle to see if that pops a standard breaker. And if it does not then check the amperage load on it with a clamp meter. If there was something wrong with the power supply it would have popped the fuses or internal circuit breaker? Sounds like you have a rush of current flowing and the GFI is tripping. And if you do not have a clamp meter purchase a device that plugs directly into the receptacle and power supply that will tell you wattage and/or amperage draw. Home depot might have one. Use them to detemine wattage on appliances for generator usage. Have a great day. Be SAFE Mac.
