Analog I/O unit, 4 x inputs -10 to 10 V, 0 to 5 V, 0 to 10 V, 1 to 5 V, 4 to 20 mA, 2 x outputs -10 to 10 V, 0 to 5 V, 0 to 10 V, 1 to 5 V, 4 to 20 mA, resolution 1:4000 scalable to ?32000 or 1:8000, screwless clamp terminal