Mini-Mite™ Tube Furnace
Operation - UT150 Controller
6
10. Use the
button to set the Al parameter to the desired
overtemperature limit in °F.
11. Press and release
SET/ENT
to advance to the P parameter
and change its value to 36.0.
12. Press and hold
SET/ENT
for 3 seconds to exit the Operating
Parameters Menu.
13. The new temperature units are now effective. Follow the
instructions in Section 6.2 to reset the temperature setpoint
in °F.
6.5
Setting the Ramp to Setpoint Rate
The Ramp Rate feature allows the chamber to be heated or
cooled at any rate slower than the maximum capability of the
unit. To fine tune ramp rates, you may need to test using
loads with similar mass and thermal properties to loads you
intend to use in furnace applications.
To set the ramp to setpoint time, complete the following steps.
If during this procedure the buttons are inactive for more than
two minutes, the controller will return to the standard display.
1. With the controller operating, press and hold
SET/ENT
for 3
seconds to enter the Operating Parameters menu.
2. Press and release
SET/ENT
until the LoC parameter is on the
upper display.
3. Press the down arrow button to show '-1', and press
SET/ENT
once to enter the Setup Parameters menu.
4. Press and release
SET/ENT
until the Upr parameter is on the
upper display.
5. Press the arrow buttons to select the new Up Ramp Rate value,
in
°C
per minute or
°
F per minute, or 'oFF'. Press and release
SET/ENT
to register the value change.
6. Press and release
SET/ENT
until the dnr parameter is on the
upper display.
7. Press the arrow buttons to select the new Down Ramp Rate
value, in
°
C per minute or
°
F per minute, or 'oFF'. Press and
release
SET/ENT
to register the value change.
8. Press and hold
SET/ENT
for three seconds to exit the Setup
Parameters menu.
9. The new Ramp Rates are now effective.
10. Follow the instructions in Section 6.2 to reset the temperature
setpoint.
To view the target setpoint during the ramp rate, press and
release an arrow button. The lower display will show the
setpoint next to the selected target setpoint. Return to the
ramping setpoint display by pressing and releasing the other
arrow button.
6.6
Auto Tuning the Controller
Factory settings are provided for general purposes, but your
process can be enhanced through the auto tune feature. For a
given process temperature and product load, auto tuning
maximizes the performance of the chamber by operating with
the quickest response and minimal temperature overshoot.
To auto tune the controller.
1. Load the chamber with materials that have the same mass
and thermal characteristics as a typical product load.
2. Operate the chamber to the process temperature.
3. Press and hold
SET/ENT
for 3 seconds to display the Al
parameter of the Operating Parameter menu.
4. Press and release
SET/ENT
to show the At parameter.
5. Press and release the arrow buttons to show on in the lower
display.
6. Press
SET/ENT
once to enter the auto tune mode and exit
the Operating Parameters menu.
The controller will cycle three times through a heating and
cooling pattern, measuring the characteristics of the load and
chamber temperature controls. During the auto tuning, At will
alternately flash with the measured temperature (PV) to indicate
that the auto tuning is in progress. The length of time for the
auto tune varies with the load, chamber size and temperature
selected.
The auto tune is completed when the regular display of the
measured temperature is shown. The chamber should now
operate to the process temperature with the given product
load, with the quickest response and minimal temperature
overshoot.
If the process temperature or load changes significantly,
another auto tune session may be necessary to optimize the
chamber performance.
Note:
T
he ramp rate begins when the SET/ENT button is
pressed after the target setpoint is selected. The setpoint
display on the controller will show the changing setpoint
at the selected ramp rate.
Summary of Contents for Mini-Mite TF550 A
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