Pulse Controller - Siemens SIMATIC S7-1200 Function Manual

2.4

Pulse controller

Two-step controllers without feedback
Two-step controllers have the state "ON" and "OFF" as the switching function. This
corresponds to 100% or 0% output. This behavior generates a sustained oscillation of
process value x around setpoint w.
The amplitude and duration of the oscillation increase in proportion to the ratio between the
delay time T
mainly for simple temperature control systems (such as electrically directly heated furnaces)
or as limit-value signaling units.
The following diagram shows the characteristic of a two-step controller
①
②
Y
h
w
PID control
Function Manual, 03/2017, A5E35300227-AC
and recovery time T
u
ON
OFF
Control range
Setpoint
of the controlled system. These controllers are used
g
Principles for control
2.4 Pulse controller
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