19
This plot shows actual data.
The green line is the temperature profile
when ramping is not used and the reaction
heats to the setpoint as normally. The red
and blue lines are the result of a ramp run.
The red line is the setpoint being ramped at a
rate of 2C/min.
The blue line is the reaction temperature that
results from this ramp.
Two features of this plot are characteristics of
ramp runs. 1) At the start of a run, the
reaction temperature almost always exceeds
the temperature of the ramped setpoint, and 2)
ramp runs overshoot the final setpoint value
by 4-5 C.
Activating & Programming the Ramp-to-Setpoint Feature
tunE
CyC.t
dAC
der.t
int.t
bAnd
oFSt
SEt.2
Soak
SPrn
SPrr
sp.lk
CyC.2
bnd.2
This is the order of controller parameters on Level 1 of the controller, when the controller is placed into programming mode (Step 1)
below.
1.
Before starting a new ramp, the controller must have the ramping feature turned off. Verify that the ramping feature is
turned off by entering programming mode and checking verifying this before continuing.
To enter programming mode, press and hold in both the ▲
and ▼ keys on the front of the temperature meter until the word
“
tunE
” appears in the display, then release both keys.
Now press the ▲ key (9 times) until the word “
SPrn
” appears in the display, then release all keys. The display on the
controller will alternate between “
SPrn
” and the word ON or OFF. If the word OFF is displayed, then exit programming
mode and proceed to Step 2. If the work ON is displayed, then hold in the ‘*’ key and press the ▼ key once to change the
display from ON to OFF, then release all keys. To exit programming mode, press and hold in both the ▲
and ▼ keys
until the temperature appears in the display, then release both keys.
2.
Note the current reaction temperature displayed by the temperature controller. Enter this temperature into the controller
as a new setpoint. For example, if the current reaction temperature is 22.5 C, then set the controller’s setpoint to 22.5 C .
3.
Press and hold in both the ▲
and ▼ keys on the front of the temperature meter until the word “
tunE
” appears in the
display, then release both keys.
4.
Press the ▲ key (8 times) until the word “
SPrr
” appears in the display.
This is where the ramp rate in units of degrees/hour is entered. First hold in the ‘*’ key, then while holding in the *’
key press the ▼ or ▲ key until the desired ramp rate appears in the display, then let go of all the keys. Units are in
degrees/hour, so if you want a ramp rate of 2C/min, then enter a value of 120.
5.
Press the▲ key once and the word “
SPrn
” will appear in the display.
This function turns the ramping feature ON or OFF. First hold in the ‘*’ key, then while holding in the *’ key press
the ▼ or ▲ key until the display shows ON (to start a ramp) or OFF (to terminate a ramp), then let go of all the keys.
6.
Press the ▲ key once and the word “
SoaK
” will appear in the display.
This is where the soak time is entered in units of minutes. A soak time of ‘ -- ‘ means to ‘soak forever’ (this setting
is one below ‘0’). First hold in the ‘*’ key, then while holding in the *’ key press the ▼ or ▲ key until the desired
time appears in the display, then let go of all the keys. If a soak time is set, the controller display will alternate
between showing the current reaction temperature and the word “
StoP
” when the soak time has expired to indicate
that power has been turned off.
7.
To exit programming mode, press and hold in both the ▼ and ▲ keys until the temperature appears in the display, then
release both keys.
Deactivating the Ramp-to-Setpoint Feature
1.
Press and hold in both the ▲
and ▼ keys on the front of the temperature meter until the word “
tunE
” appears in the
display, then release both keys.
2.
Press the ▲ key (9 times) until the word “
SPrn
” appears in the display.
This function turns the ramping feature ON and OFF. First hold in the ‘*’ key, then while holding in the *’ key press
the ▼ or ▲ key until OFF appears in the display, then let go of all the keys.
3.
To exit programming mode, press and hold in both the ▲
and ▼ keys until the temperature appears in the display, then
release both keys.
Reaction temperature exceeds the
value of the ramped setpoint.
Ramp runs typically over-shoot
the setpoint by a greater amount
than standard runs do.
