Overview Of The Internal Signal Flow; Table 20 Overview Of The Internal Signal Flow - WAGO 750 Product Manual

Functions

4.4.2 Overview of the Internal Signal Flow

Signal
User setpoint
Trigger
Ramp generator
Zero point offset
Linearization
Valve adjustment
Dither generator – automatic
amplitude adjustment
Dither generator
Dither generator – DC correction A measured DC current deviation with activated dither is compensated.
Valve adjustment – limitation
Nominal current
Dither generator – filter
PID controller
PWM
Valve
Current measurement
Actual value, output (Vx_AC-
TUAL)
44 Product manual | Version: 1.1.0
Proportional Valve Module 2-3-4
Explanation
Setpoint specification by the user via the process image (Vx_SETPOINT) or
in JOG/TIP mode
Below the adjustable trigger value, the value 0 is output.
Above the adjustable trigger value, the input value is output.
Implements a ramp, from the active process value to the desired final value
Application of a ± offset value to the input value
Linearizes the input value using a parameterizable characteristic consisting of
several supporting points
Defines a minimum output value #MIN and a maximum output value #MAX
between which the input value is adjusted
The dither amplitude is automatically limited during operation to avoid an
asymmetrical signal in the current limiting range.
Generates a square-wave or sinusoidal signal that is applied to the signal
Limitation of the signal by the #MIN and #MAX limits from the "Valve adjust-
ment" function block
Conversion of the relative setpoint (%) into an absolute setpoint (A)
Filtering of the measured actual current so the dither signal can be filtered out
Digital PID current controller for the output current
PWM signal required for control of the H-bridge
Connected proportional valve
Measurement amplifier that amplifies the voltage across the shunt resistor,
allowing the voltage to be converted to current
Application of calibration values to the measured current value
Measured and filtered actual value of the output current, which can be read
out via the process image
750-1632/000-100
Table 20: Overview of the Internal Signal Flow