Fisher DPR900 User Manual page 75

Configuration
5-21
5.6.3.3 Deviation Alarm Limits
The DPRSOO is capable of externally indicating setpoint deviation
alarms, provided that absolute alarms have not been selected.
Configure setpoint deviation alarms using FCODE 104. The controller
measures deviation and activates deviation alarms for the process
value relative to the current setpoint value as shown in the figure.
These alarms have a hysteresis of 1 percent of the configured range. 1
Function FCODE Option
NO Default Selected
Value Value
Deviation 104 Disabled
0 0
Alarm Enabled
1
Selection
- Positive -
DO4 is activated
Deviation
DO4 is deactivated
and H flashes and H stops flashing
PV alarms, setpoint deviation alarms, sensor
status, and setpoint ramping all use DO3 and DO4
and are mutually exclusive. If more than one of
these functions is set at a time, the display flashes
ERROR.
Use FCODE 5 to set the setpoint negative deviation limit in the range
0 to the lower measuring range limit.
Use FCODE 6 to set the setpoint positive deviation limit in the range 0
to the upper measuring range limit.
Function Parameters
Deviation Negative limit
Alarm Positive limit
Limits
FCODE Range
Unit
Increment Default Selected
Value Value
5
W-W
a"Y
1 digit -Ma
6
'W+M) any
1 digit +Max
Brightly lit bars on the process value bargraph indicate the setpoint
deviation alarm limits. The deviation alarm limits interact with the
setpoint value and change automatically if the setpoint value is
altered.
Change 2 -July 1992