Two-Step Control - Siemens SIMATIC S7-1200 Function Manual

Instructions
9.4 PID basic functions
9.4.3.5

Two-step control

In two-step control, only the positive pulse output QPOS_P of PULSEGEN is connected to
the on/off actuator. Depending on the manipulated value range used, the two-step controller
has a bipolar or a unipolar manipulated value range.
Two-step control with bipolar manipulated variable range ( -100% to 100%)
Two-step control with unipolar manipulated variable range ( 0% to 100%)
The negated output signal is available at QNEG_P if the connection of the two-step controller
in the control loop requires a logically inverted binary signal for the actuating pulses.
Pulse
QPOS_P
QNEG_P
468
Actuator On
TRUE
FALSE
Actuator Off
FALSE
TRUE
Function Manual, 03/2017, A5E35300227-AC
PID control