DH

Machine and Alarm list	Description	Cause	Action	Class
DH A1 Over temperature	If the temperature is more than 15C° above the setpoint for 1 min., an alarm appears.	The temperature has been adjusted from a high temperature to a lower temperature, this triggers the "Over temperature" alarm. Malfunctioning sensor.	Give it a few minutes to cool down the air and the alarm will disappear. Check if the sensor is working correctly or is short-circuited.	Alarm
DH A2 Under temperature	If the temperature is 10C° below the setpoint for 10 min., a warning appears.	Too high temperature setpoint. The heating element is malfunctioning. Signal to the heating element is missing. Malfunctioning sensor.	Adjust temperature setpoint to lower setpoint. If a higher temperature is needed, contact Labotek Service/Sales department. Check if the heating element is malfunctioning. Check if the signal to the heating element is correct. Are the Solid-state relays activated? If not, check if the ASI module output is activated. Is it activated - check the cable connection from the ASI module, all the way to the heating element to see, if it is correctly connected. If it is not, contact Labotek Service department. Check if the sensor is working correctly or is short.	Warning
DH A3 Sensor fault dry air	The alarm is activated if the Pt-100 sensor in the inlet air is disconnected / short-circuited. The alarm turns off the supply of heat.	Malfunctioning sensor.	Check if the sensor is working correctly or is short-circuited.
DH A4 Sensor error return air	The alarm is activated if the Pt-100 sensor in the outlet air is disconnected / short-circuited. The alarm provides only information at the display.	Malfunctioning sensor.	Check if the sensor is working correctly or is short-circuited.
DH Regeneration time 2 is too long	If the regeneration time is longer than 60 min. on molecular sieve 2, a warning appears.	See alarm: REG. TIME 1 IS TOO LONG.	See alarm: REG. TIME 1 IS TOO LONG.	Warning
DH / Optional alarm A5 Parameter Error Ext. PAR	The alarm is activated if the option Ext. PAR is used and the parameter value for the setpoint is outside the scaling area.	The parameter value for the setpoint is outside the scaling area.	Check if the scaling / IO from the customer is correct.
DH Fire protection	If the fire protection is triggered an alarm appears and the heating stops.	The temperature setpoint is too high compared to the thermostat on the backside of the DH. Malfunctioning thermostat.	Reset thermostat on the backside of the DH (turn off the DH cabinet and turn the thermostat to max temperature and click the small reset button in the little hole). Adjust the thermostat to the correct temperature and adjust the correct temperature setpoint for the DH. Check if the thermostat is working correctly or is short-circuited or the wire is broken.	Alarm
DH / Optional alarm High level	If the level sensor is activated or not activated (depends on the function) a warning appears. Tells the operator (depending on the function), if the material is at / not at this level in the hopper.	Shows wrong value. The sensor is malfunctioning.	Check wiring connections to sensor. Check if the signal is reversed. Check if the sensor is working correctly.	Warning
DH / Optional alarm Middle level	If the level sensor is activated or not activated (depends on function) a warning appears. Tells the operator (depending on the function), if the material is at / not at this level in the hopper.	Shows a wrong value. Sensor is malfunctioning.	Check wiring connections to sensor. Check if the signal is reversed. Check if the sensor is working correctly.	Warning
DH / Optional alarm Low level	If the level sensor is activated or not activated (depends on the function) a warning appears. Tells the operator (depending on the function), if the material is at / not at this level in the hopper.	Shows a wrong value. Sensor is malfunctioning.	Check wiring connections to sensor. Check if the signal is reversed. Check if the sensor is working correctly.	Alarm
DH Black display	See alarm: Fire Protection	See alarm: Fire Protection.	See alarm: Fire Protection.	Alarm

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