KAESER KOMPRESSOREN SX, Service Manual, Page: 35 / 122

DUAL
In the DUAL control mode, the machine is switched back and forth between LOAD and IDLEto main‐
tain pressure between the preset minimum and maximum values. When maximum pressure is
reached, the machine switches to IDLE. When the preset
idling time has elapsed, the machine
switches to STANDSTILL.
The
idling time is fixed in SIGMA CONTROL BASIC.
QUADRO
In the QUADRO mode, the controller operates as in the DUAL mode during periods of high air demand
by switching between LOAD and IDLE, but during periods of low air demand it switches directly to
STANDSTILL.
This mode of control requires two pre-set time periods: the
running time and the idle/standstill time.
The
idling/standstill time and the running time are set in SIGMA CONTROL BASIC.
MODULATINGcontrol
MODULATINGcontrol is based on the DUALcontrol mode. The difference to DUAL is that the air
delivery is continuously varied within the control range of the machine.
This control mode is not available on variable speed machines with a frequency-controlled
drive (SFC).
Compressed Air Demand Operating modes
rises MODULATING
LOAD
falls MODULATING
IDLE
STANDSTILL
Tab. 31 Operating modes under MODULATING control
4.7 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 stop‐
ped. The pressure system is vented.
■ Pressure relief valve:
The pressure relief valve protects the machine from excessive pressure. It is preset at the factory.
■ Door interlock switches:
The machine will stop automatically if a door or panel fitted with these safety interlocks is opened
or removed.
■ Enclosures and guards for moving parts and electrical connections:
These protect against accidental contact.
4 Design and Function
4.7 Safety Devices
9_6919 04 E
Service Manual Screw Compressor
SX SIGMA CONTROL BASIC
25
Option C1