4.9 Auto, Manual and Off Mode

 

In Level 2, the controller can be put into Auto, Manual or Off mode.

 

Auto mode is the normal operation where the output is adjusted automatically by the controller in response to changes in the measured value (temperature).

 

In Auto mode all the alarms and the special functions (for example, auto tuning and timer) are operational.

 

Manual mode means that the controller output power is manually set by the operator. The input sensor is still connected and reading the temperature but the control loop is ‘open’.

 

In Manual mode all the alarms are operational.

 

In manual mode the MAN beacon will be lit, the auto-tuning and timer functions are disabled.

 

The power output can be continuously increased or decreased using the or buttons.

 

Warning: Manual mode must be used with care. When in Manual, the power level must not be set and left at a value that can damage the process or cause over-heating. The use of a separate ‘over-temperature’ controller is recommended.

 

Off mode means that the heating and cooling outputs are turned off. The High, Low and Deviation alarms will be OFF. The analogue retransmission outputs will, however, still be active.