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When set to the window function, the upper limit value (FH) and the lower
limit value (FL) have a fixed hysteresis 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�
4.3 Analogue output
The unit provides an analogue signal that is proportional to the volumetric flow
quantity, the medium temperature or the pressure�
Within the measuring range the analogue signal is 4���20 mA�
The measuring range is scalable:
• [ASP2] determines at which measured value the output signal is 4 mA�
• [AEP2] determines at which measured value the output signal is 20 mA�
Minimum distance between [ASP2] and [AEP2] = 20 % of the final value of
the measuring range�
If the measured value is outside the measuring range or in the event of an internal
error, the current signal indicated in Fig� 1 is provided�
For measured values outside the display range or in case of a fault, messages are
displayed (cr�UL, UL, OL, cr�OL, Err;
)�
The analogue signal in case of a fault is adjustable
• [FOU] = On determines that the analogue signal goes to the upper final value
(21�5 mA) in case of an error�
• [FOU] = OFF determines that the analogue signal goes to the lower final value
(3�5 mA) in case of an error�
• [FOU] = OU defines that in case of a fault the analogue signal reacts as defined
by the current parameters�