given the essence of time, I will be getting the amazon linked cable (c19) and will hope my local hardware store has the 6-30 cable. No one seems to sell just the 6-30 plug thats not the locking type. Any idea if the two wires linked are safe to connect to one another? One is 10 awg (the NEMA 6-30 cable) and the C19 cable is 12 awg.