4�5 Switching Function; Window Function - Autosen AS005 Notice D'utilisation

4.5 Switching function
OUTx changes its switching status if it is above or below the set switching limits
(flow or temperature)� Hysteresis or window function can be selected� Example of
flow monitoring:
Hysteresis function
SP
rP
SP = set point
rP = reset point
HY = hysteresis
Hno = hysteresis NO (normally open)
Hnc = hysteresis NC (normally closed)
When the hysteresis function is set, the set point SP and the reset point rP
are defined� The rP value must be lower than the SP value� The distance
between SP and rP is at least 4 % of the final value of the measuring range
(= hysteresis)�
If only the set point is changed, the reset point is changed automatically;
the difference remains constant�
When set to the window function the upper limit value FH and the lower
limit value FL are defined� The distance between FH and FL is at least 4 %
of the final value of the measuring range�FH and FL have a fixed hysteresis
of 0�25 % of the final value of the measuring range� This keeps the swit-
ching status of the output stable if the flow rate varies slightly�
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Window function

FH
FL
FH = upper limit value
FL = lower limit value
FE = window
Fno = window NO (normally open)
Fnc = window NC (normally closed)