4.8 Safety devices
The following safety devices are provided and may not be modified in any way.
■ EMERGENCY STOP control device:
The EMERGENCY STOP button shuts down the compressor immediately. The motor remains
stopped. The pressure system is vented.
■ Pressure relief valve:
The pressure relief valve protects the system against excessive pressure. It is factory set.
■ Safety pressure switch (machine with refrigeration dryer):
The safety pressure switch protects the refrigerant circuit against excessive pressure. It cannot
be set.
■ Door interlock switches:
The machine will stop automatically if a safety interlocked door or panel is opened or removed.
■ Enclosures and guards for moving parts and electrical connections
Protect against accidental contact.
4.9 Keys and LEDs – SIGMA CONTROL BASIC
Fig. 7 Keys – overview
Item
Name
Function
1
«ON»
Switch on the machine.
2
«OFF»
Switch off the machine.
Resets alarms (acknowledge).
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
4.8
Safety devices
9_5717 20 E
Service Manual Screw Compressor
ASK T SIGMA CONTROL BASIC
33
