Endress+Hauser Flowphant T DTT31 Flowphant T DTT35 Operating Instructions Manual page 19

Flowphant T DTT31, DTT35
6. NOK: The switch point determined is under 5 % of the measuring range and cannot be
accepted because the switch point must be at least 5 % greater than the switchback
point (RSP).
The device is still operative if message "W432" or "NOK" is displayed. There can be large
deviations at the switch point, however. Recommendation: Repeat the learning process
(points 1 to 4) until "OK" appears on the display.
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Operation options
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