To elaborate further on p-funk's post, i'll provide some examples
Squat - 3/2/1/1 (3 sec ecc, 2 sec in the hole, 1 sec conc, 1 sec pause) then repeat
Bench - 5/3/1/1 (5 sec ecc, 3 sec iso, 1 sec conc, 1 sec pause)
Usually you will want to keep the concentric at 1 second. There is no point in doing slow concentrics.