Depends on what you intend to run with it, how far it will travel, and what amp rating you will be running from. BTW, no 30A TT can handle all appliances at one time. You can run a grand total of 3600 watts of devices. An electric space heater (1500 watts) would require a 20 amp circuit to avoid issues and I would use #12 wire with a ground. (12-2 w/ground). I do not know the distance that will be safe for, someone with first hand Elec/code knowledge would have to answer that.