Quote Originally Posted by pjfossee View Post
... what does the 11 amp rail power. Just the heat bed? If I am using a relay then can I expect that there will never be the whole 11 amps drawn from that rail?
On RAMPS, the 11-amp input *only* sources power for whatever is connected to the D8 output, which is usually the heat bed. If you're using a heat bed relay, D8 would only need to supply a small amount of current to energize the relay. #20 wires would be more than fine for that, as would just adding short jumpers from the 11-amp input to the 5-amp input.