3.10.1 Ramp Function
If the ramp control function is enabled, the process will increase or decrease at a predetermined rate
during initial power up, or with setpoint changes/process variations.
The ramp rate is determined by the " rr " parameter which can be adjusted in the range 0 to 200°C/
minute. The ramp rate function is disabled when the " rr " parameter is set to " 0 ".
In the example below the Ramp Rate is
set to 5°C/min, power is applied at zero
time and the process value climbs to the
125°C setpoint over a period of 20 minutes.
control
This process temperature is held until the
setpoint value is changed to 150°C at 40
set point
minutes. The process value then climbs
to the new setpoint over a period of five
minutes and the new setpoint is held. At
70 minutes, the setpoint value is
decreased to 75°C and the process values
t (10')
falls to the new setpoint over a period of
15 minutes.
3.10.2 Ramp & Soak Function
The soak function is enabled by configuring the alarm output to act as a dwell timer. The para-meter
" ALm1 " needs to be set to the value 12. The alarm contact will now operate as a timer contact, with the
contact being closed at power up and opening after the elapsed time set at parameter " ASP1 ".
If the controller power supply or output is
wired through the alarm contact, the
controller will operate as a guaranteed
Control
soak controller.
In the example below the Ramp Rate is
set to 5°C/min, " ALm1 " = 12 and " ASP1 "
= 9 (minutes). Power is applied at zero time
and the process climbs at 5°C/min to the
Alarm
setpoint of 125°C. Upon reaching setpoint,
the dwell timer is activated and after the
soak time of 9 minutes, the alarm contact
t (10')
will open, swit-ching off the output. The
process temperature will eventually fall at
an undetermined rate.
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