Control action

On valves where the stem retracts to the close position, "direct acting" means that the value is fully closed at positioning signal Y = 0 V or Z = 0 Ω (i.e. 0 %).

Direct acting

Positioning signal Y

DC 0...10 V, 4...20 mA

Positioning signal Z

0...1000 Ω

Y, Z

Positioning signal

V

Volume flow

Control action: Direct acting