Emerson Rosemount 1408A, Справочное руководство

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Low alarm
Enable or disable the low alarm.
Alarm set points
SP1 - High alarm set point
If the measured value is above this set point, the digital output is set to alarm state.
SP2 - Low alarm set point
If the measured value is below this set point, the digital output is set to alarm state.
Hysteresis
The hysteresis is a buffer zone so the alerts do not toggle on and off when the
measurement value fluctuates around the alarm limit. The alarm is set when the value
exceeds the alarm limit. The alarm is then cleared when the value falls outside the
hysteresis zone.
SP1 - Hysteresis high alarm
Hysteresis zone for the high alarm.
SP2 - Hysteresis low alarm
Hysteresis zone for the low alarm.
C.4 Analog output
C.4.1 Analog control variable
Select between volume flow or level to control the analog output.
C.4.2 Upper/lower range value
Enter the range values that correspond to the analog output values 4 and 20 mA. In
normal operation, the transmitter will drive the output in response to volume flow or level
from the lower to upper saturation points.
Note
The 20 mA point should be set below the reduced accuracy zone at the top of the tank.
Reference Manual Configuration parameters
00809-0200-4480 May 2021
Reference Manual 83