Control mode Advantage
Disadvantage
TIMER
Lower power consumption when
the compressor is shut down
Brief increase in dew point when the compres‐
sor re-starts
Tab. 23 Refrigeration dryer control modes
4.9 Safety Devices
The following safety devices are provided and may not be modified in any way:
■ «EMERGENCY STOP» button,
The «EMERGENCY STOP» button shuts down the machine immediately. The motor remains
stopped. The pressure system is vented.
■ Safety relief valve:
The safety relief valve protects the machine from excessive pressure. This is factory set.
■ Door interlock switches:
The machine will stop automatically if a safety interlocked door or panel is opened or removed.
■ Enclosures and covers for moving parts and electrical connections:
These protect against accidental contact.
4.10 SIGMA CONTROL BASIC Keys and Indicators
Fig. 12 Keys
Item
Description
Function
1
«ON»
Switches the machine on.
2
«OFF»
Switches the machine off.
Resets alarms.
Resets the maintenance interval counter.
6
«DOWN»
Scrolls down the parameter list.
Reduces a parameter value.
7
«UP»
Scrolls up the parameter list.
Increases a parameter value.
8
«escape»
Exits the edit mode without saving.
4
Design and Function
4.9
Safety Devices
Number: 9_6945 01USE
Service manual Screw compressor
Aircenter SX 3/7.5 SIGMA CONTROL BASIC
27
