4.4.2 Control modes
Using the selected control mode, the controller switches the machine between its various opera‐
tional states in order to maintain the gauge working pressure between the set minimum and maxi‐
mum values, regardless of the drawn compressed air volume. The control mode also rules the de‐
gree of energy efficiency of the machine.
The shortest possible times for the various parameters is preset by the factory to ensure that the
compressor motor earlier and more frequently is at standstill. If you want to change these parame‐
ters, select the shortest possible times in order for the machine working energy-efficiently.
The machine-dependant venting time between the LOAD and READY operating modes ensures
load changes at minimum material stresses.
The following control modes can be set:
■ DUAL
■ QUADRO
■ VARIO
Supplementary mechanical flow rate regulation:
■ MODULATING control
Energy-efficient control modes for various applications:
Application
Recommended
control mode
Compressed air station with one machine or several machines supplying
similar volumes.
VARIO
Machine for peak load in a compressed air station
DUAL
Machine for intermediate load in a compressed air station
VARIO
Machine for basic load in a compressed air station
QUADRO
Tab. 22 Energy-saving control modes
The QUADRO control mode is preset by the factory, unless a different agreement has been made
with the manufacturer.
DUAL
In the DUAL control mode, the machine is switched back and forth between LOAD and IDLE to
maintain the machine working 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 READY.
QUADRO
Unlike DUAL control mode, in QUADRO the machine will switch between LOAD to READY after
short periods of being in IDLE.
Following extended times in the various operating modes, the machine switches from LOAD to
READY.
In this event, the controller considers the time in READY mode as
standstill time. The time in LOAD
and IDLE operating modes are taken as
minimum runtime.
4
Design and Function
4.4
Operating modes and control modes
26
Operator Manual Screw Compressor
SM Tri-Voltage, SIGMA CONTROL 2
9_5875 33 USE
Option C1
