The Grinder pumps are operated by control panels with variable level see that float control switches will not hang up on the grinder pump ... Rotor I840 2 3450 200 1 60 20.0 6.6 12.1 60 H 1.0 / 1.5 E840 2 3450 230 1 60 17.2 4.0 10.9 56 F 1.3 / 4.0 J840 2 3450 200 3 60 12.3 3.7 7.7 54 L 1.9