Armed with the design ideas of block structure and Multi-port type, we produced the IS-EP 1000 series E-P valve positioner which has two types, one is Linear and another is rotary. The Linear one is used for linear operation of pneumatic linear valve actuator. The rotary one is used for rotary pneumatic actuator. They control valve stroke accurately, through pressure air, according to input signal of 4-20mA being input from electrical controller control system.