Fisher DPR900 User Manual page 88

5-34
Configuration
(FISnER;
I
I
I
0%
Manual 1
Auto
AU10
t Time
t0 t1
k! DPR900433
The heating time is 7 hours (420 minutes) and:
n
The measuring range is -50 to 600 degrees C,
n
The current process value is 90 degrees C
H The final setpoint value is 300 degrees C.
The process must heat to 210 degrees C in 420 minutes, giving a
ramp of 0.50 degrees C/minute. The figure shows the heating time
between to and tl.
At to the setpoint value equals the process value. The controller
ramping algorithm moves the setpoint value at a constant speed to
the preset value during to to tl. The PID parameters are not
influenced by the ramp speed, and the actual value follows the
changing setpoint value throughout the ramping.
The ramp starts when the controller switches from manual to auto, to,
When the controller is switched to auto, the setpoint ramping starts at
the present process value, moving at the preset speed towards the
final setpoint.
DO3 and DO4 indicate the ramp status when FCODE 109 is set to 1.
DO3 is active during ramping, from to to t,. DO4 is active at tz,
indicating that the configured time period is elapsed.
While the ramp is in control, the digital display shows the
instantaneous value of either the process value or the setpoint,
depending on the configuration. The final setpoint value displays as a
brighter bar on the bargraph and the PV and SP bargraphs also show
the instantaneous values.
To alter the setpoint value while the ramp is active, switch the
controller to manual mode. Insert the new setpoint value and restart
the ramp with the new parameters.
lJM6.1:LlPR900:9147
Change 2 -July 1992