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VPPM-MPA: Proportional technology on the fieldbus

VPPM-MPA enhances the CPX/MPA by adding various pneumatic and electrical functions

The benefits to you:

3 presets can be selected via CPX: quick, universal, precise
Diagnostics on the fieldbus: all values, as well as upper and lower limits, can be remotely controlled and monitored via VPPM-MPA.
Individual pressure and force control on multiple actuators and processes using digitised analogue values – communicated via fieldbus/Ethernet
Variable MPA pressure zones: one VPPM – different pressures, can also be sequentially switched for multiple MPA connection blocks
Commissioning without fieldbus – via the handheld terminal CPX-MMI

Terms for proportional-pressure regulator
Response sensitivity	The response sensitivity of the device determines how sensitively a pressure can be changed or (in other words) set. The smallest differential in setpoint value which is able to change the output pressure is referred to as the response sensitivity. In this case it is 0.01 bar.
Pressure range adaptation	On delivery, 100% setpoint value equals 100% fluid output signal. The pressure range adaptation or adjustment makes it possible to match the fluid output variable to the setpoint value.
Hysteresis	Within a certain tolerance, there is always a linear relationship between the setpoint value entered and the pressure output. Nevertheless, there is a difference between whether the setpoint value entered is increasing or decreasing. The difference in maximum deviations is referred to as hysteresis.
Linearity error	The perfect linear trend of the control characteristic of the output pressure is theoretical. The maximum percentage deviation from this theoretical control characteristic is referred to as the linearity error. The value is expressed as a percentage of the maximum output pressure. (Full scale)
Zero point suppression	In real-world applications, it is possible for there to be a residual voltage or residual current at the setpoint input of the VPPM via the setpoint generator. The zero-point suppressor is used so that the valve is reliably vented at setpoint zero.
Repetition accuracy (reproducibility)	The repetition accuracy is the margin within which the fluid output variable is scattered when the same electrical input signal coming from the same direction is repeatedly adjusted. The repetition accuracy is expressed as a percentage of the maximum fluid output signal.