4.0 2132 Over-Temperature
4.2.2
Operation
When switched on, the controller lights up, goes through a short test routine and then
displays the measured temperature or the over-temperature setpoint.
The page key
allows access to parameter lists within the controller.
A single press of the page key
displays the temperature units, normally set to °C;
further presses reveal the lists indicated in the navigation diagram. See section 4.4.
The scroll key
allows access to the parameters within a list. Some parameters are
display-only; others may be altered by the operator.
A single press of the scroll key
in the 'Home' list displays the temperature units;
further presses reveal the parameters in the current list indicated in the navigation
diagram.
To return to the 'Home' list at any time, press page
and scroll
together, or wait
for 45 seconds.
The down
and up
keys are used to alter the setpoint or other parameter values.
4.2.3
Over-Temperature Operation
Use down
and up
to alter the over-temperature setpoint. This should normally be
set a little above the working temperature (for example 15 °C above). The product is
supplied with the over-temperature set at 15 °C above the furnace or oven maximum
working temperature.
Press scroll
twice view the present temperature as measured by the over-
temperature controller. Press it twice, the first press shows the temperature units (°C).
4.2.4
Over-Temperature Alarm
If an over-temperature condition occurs, the OP2 indicator flashes and an alarm
message 2FSH also flashes, alternating with the setpoint. Power to the heating
elements is disconnected.
4.2.5
Resetting the Over-Temperature Alarm
To acknowledge the alarm press scroll
and page
together.
If the alarm is acknowledged while there is still an over-temperature condition, the OP2
indicator stops flashing but continues to glow. The 2FSH alarm continues to flash until
the over-temperature condition is cleared (by the temperature falling), when normal
operation resumes.
If the alarm is acknowledged when the temperature has dropped (or after the over-
temperature setpoint has been raised) so that the over-temperature condition no longer
exists, then the furnace or oven immediately resumes normal operation.
4.2.6
Sensor Break
The over-temperature cut-out system also operates if the over-temperature control
thermocouple breaks or becomes disconnected. The message S.br flashes where the
measured temperature is normally displayed.
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