Body

Operating the Temperature Controllers (Large Cell)

There are identical control setups for each cell. These consist of a programmable temperature controller and a limit controller. The limit controller shuts down the heating supply if the equipment temperature exceeds the limit set-point chosen or if there is an electrical short in a thermocouple or thermocouple wire. The procedure for turning on the system, setting up a temperature program, and starting up the system is as follows:

  • Turn on the instrument power for the appropriate cell and the equipment power in the circuit breaker box in the middle of the panel board.
  • Set the thermocouple selector switches under the temperature controller and limit controller for the appropriate thermocouples.
  • Set the heater output selector switch above the controllers to the appropriate equipment.
  • Check to see that the display of the temperature controller is flashing alternately a temperature and "off". If not, the power was turned off before the run was terminated and the previous run must be terminated by first pressing the run/hold key, then pressing the scroll key →arrowcircle
    until "off" is displayed, and next pressing the "down" key.
    Note: Adjustments on the temperature controller must be made within five seconds of each other or the controller will return to the starting point in the software tree.
  • Press the scroll key on the temperature controller several times until "Pent" (parameter entry) is displayed.
  • Press the down key to enter the software within the parameter entry.
  • Press the scroll key through the settings and make adjustments by pressing the "up" and "down" keys on the parameters in italics as needed (do not change the other parameters)., the following is an example for setting the controller to heat from room temperature to 250 °C over 3 hours and to shut off after being at 250 °C for 24 hours:
Table III. Example for Setting Controller
Display Setting Description
Pn 1 Profile number
RS 1 Run segment
Rt 3.00 Ramp time in hours
SP 250 Set point in Celsius
ST 24.00 Soak time in hours
PLCt 1 Profile loop count
Dhru 1  
Dhrd 0.0  
Pend 0 Program end
Table IV. Profile Number Reservations
Profile # Large Rocker Small Rocker
1    
2 Yoonkyung Yoonkyung
3    
4    
5    
6   Raj
7    
8 Hardas-OpTest Hardas-OpTest
     
  • Return to the top of the software tree by pressing the "up" key while one of the parameter names (Pn, rS, rt, etc.) is being displayed.
  • Scroll through the parameters again to make sure that they are set correctly.
  • Adjust the limit set-point on the limit controller while holding the toggle switch in the direction of the "Set II" setting.
  • Reset the contacts for the heating circuit by pressing the reed "start" button to the above right of the controllers.
  • Scroll to Pn on the temperature controller (where n=your profile #) and press the run/hold key.
  • Be sure to stay around long enough to see that the equipment is indeed heating up. You should notice a change in temperature of at least 5 °C on each controller before assuming that everything is set properly.
  • After the total run time (ramp time plus soak time), the heat will turn off. Be sure to let the temperatures cool down sufficiently before attempting to open or depressurize a reaction vessel. Also remember to turn off the power to the equipment and instruments in the circuit breaker box when you are finished.
  • If you need additional information on operating the temperature controllers, please consult the temperature controller manuals in another section of this lab manual.