Vaisala BAROCAP PTB330, Руководство пользователя

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User's Guide ______________________________________________________________________
90 __________________________________________________________________ M210855EN-C
0610-076 Figure 41 Relay Output Modes
Mode 4 is usually used if an alarm needs to be triggered when the
measured value exceeds a safe range. The relay is active when
measurement is in range, and is released if the value goes out of range
or the measurement fails.
Hysteresis
The hysteresis function prevents the relay switching back and forth
when the measured value is near to the setpoint values.The relay is
activated when the measured value passes the exact value of the
setpoint. When returning to and passing through the setpoint again, the
relay is not released before the value reaches the setpoint increased/
decreased by the hysteresis value, see
Figure 41 on page 90 . The
hysteresis should be smaller than the difference of the setpoints.
NOTE
If the measurement of the selected quantity fails or the barometer loses
its power, the relay is released.