6
Controller Operation
This chapter discusses in detail how to operate the furnace temperature control-
ler using the front control panel. Using the front panel key-switches and LED
display the user may monitor the well temperature, set the temperature
set-point in degrees C or F, monitor the heater output power, adjust the control-
ler proportional band, set the cut-out set-point, and program the probe calibra-
tion parameters, operating parameters, serial and IEEE-488 interface
configuration, and controller calibration parameters. Operation of the controller
functions is summarized in Figure 6.
In the following discussion a solid box around the word SET, UP, EXIT or
DOWN indicates the panel button while the dotted box indicates the display
reading. Explanation of the button or display reading are to the right of each
button or display value.
6.1
Well Temperature
The digital LED display on the front panel allows direct viewing of the actual
well temperature. This temperature value is what is normally shown on the dis-
play. The units, C or F, of the temperature value are displayed at the right. For
example,
100.00 C
Well temperature in degrees Celsius
The temperature display function may be accessed from any other function by
pressing the “EXIT” button.
6.2
Reset Cut-out
If the over-temperature cut-out has been triggered, the temperature display al-
ternately flashes,
Cut-out
Indicates cut-out condition
This message continues to flash until the temperature is reduced and the cut-out
is reset.
The cut-out has two modes — automatic reset and manual reset. The mode de-
termines how the cut-out is reset which allows the instrument to heat up again.
When in automatic mode, the cut-out resets itself as soon as the temperature is
lowered below the cut-out set-point. When in manual reset mode the cut-out
must be reset by the operator after the temperature falls below the set-point.
When the cut-out is active and the cut-out mode is set to manual (“reset”), the
display flashes “cut-out” until the user resets the cut-out.
To access the reset
cut-out function press the “SET” button.
23
6 Controller Operation
Well Temperature
