A.C. power connectors ? something better than 4 pin xlr ?

I have a couple of 1ru cases that are too crammed so i'm planning on mounting the transformer in a separate box and then running the low voltage a.c. to the rack [ with the regulators still on board so it's not a
huge multi pin cable going to the rack .

I have a few 4 pin xlr type connectors but noticed some people were using different connectors [ smaller round 3 pin ? ] where from ?

Any opinions / experience n other things ? what does everyone do about the chasis ground ? [ run it there as well ? ]

thanks in advance , regards Greg