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4.5.1 Hysteresis function
rP
Normally open: [OUx] = [Hno]
Normally closed: [OUx] = [Hnc]
First the set point (SPx) is set, then the
reset point (rPx) with the requested
difference�
When SPx is adjusted, rPx is
changed automatically; the differ-
ence remains constant�
Example of volumetric flow monitoring
HY = hysteresis
4.5.2 Window function
Normally open: [OUx] = [Fno]
Normally closed: [OUx] = [Fnc]
The width of the window can be set by
means of the difference between SPx
and rPx�
SPx = upper value
rPx = lower value
Example of volumetric flow monitoring
FE = window
When set to the window function the set and reset points have a fixed hys-
teresis of 0�25 % of the final value of the measuring range� This keeps the
switching status of the output stable if the volumetric flow varies slightly�