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Single Channel Profile: See graph on following page.
In this example the 620A is in the single channel mode and operating as a temperature only
system. The controller units are in degrees C and three events are assigned as:
Circulator – event 1, heat – event 2 and cool – event 3.
We have chosen 2 deg C/min as a ramp rate. To determine the ramp time we divide the ramp
range by 2. The result is the step time entered in the program step.
Profile: The profile starts at 25 deg C. Events 1, 2 & 3 will be programmed "on" for each step.
Steps 1 and 2 are for conditioning the chamber to 25C.
Step 1 Ramp/Soak: Ramp from current chamber temp to 25 C in 1 minute and wait for the
process temp to be within 1 deg C (GS1 = 1) of the 25 C setpoint before advancing to
step 2.
Step 2 Ramp/Soak: Soak or dwell at 25 C for 15 minutes to allow the internal chamber temp to
stabilize close to 25 C.
Step 3 Ramp/Soak: Ramp the temp from 25 C to 85 C in 30 minutes and wait for the process
temp to be within 2 deg C (GS1 = 2) of the 85 C setpoint before advancing to step 4.
NOTE: Ramp range, 85 – 25 = 60 C, 60/2 (ramp rate) = 30 minutes.
Step 3 will be our "Loop to" step later in the profile.
Step 4 Ramp/Soak: Soak at 85 C for 2 hours.
Step 5 Ramp/Soak: Ramp from 85 C to -35 C in 1 hour and wait for the process temp to be
within 2 deg C (GS1 = 2) of the -35 C setpoint before advancing to step 6.
(Ramp range, 85 – (-35) = 120 C, 120/2 (ramp rate) = 60 minutes.
Step 6 Ramp/Soak: Soak at -35 for 2 hours.
Step 7 Ramp/Soak: Ramp from -35 C to 25 C in 30 min., and wait until for the process temp to be
within 2 deg C (GS1 = 2) of the 25 C setpoint before advancing to step 8.
(Ramp range, 25 – ( -35) = 60 C, 60/2 (ramp rate) = 30 minutes.
Step 8 LOOP: Loop back to step 3, for 50 loops (passes)
NOTE: The number of loops entered includes the first pass.
Step 9 Ramp/Soak: This is a 15 minute soak step at 25 C following the final loop.
This allows the chamber to stabilize at ambient temperature prior to shutting it down.
The desired soak time will be determined by the user for the size of the chamber
and the prior soak step temperature.
Step 10 Ramp/Soak: This step is used to clear the controller setpoint, killing the controller outputs.
This step is optional. If this step was not entered, the step 9 Setpoint and event
parameters would be latched when the EOP step ends the program.
Step 11 EOP: Every program "Must" be terminated with an EOP step.
Similar to the Loop step, the EOP step can cycle back to a desired step.
When the EOP Cycle (Loop) counter reaches zero the program ends.
When the EOP cycle counter reaches zero the previous step's setpoint and event
status are latched.
In our example we entered 50 loops. The first time the loop step is accessed
the counter is decremented to 49. If the loop counter is greater than 0 we
loop back to step 3. If the loop counter is equal to zero we proceed to the
next programmed step. The LOOP counter default is 1.
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