The ideal coolant pre-heating period is 2-3 hours before the machine is started. A pre-heating period
of more than 3 hours is not necessary, as the maximum effect has already been achieved within this
period (thermal balance).
4.11 Option ga
Generator option
A generator is installed to provide a power supply to electrical consumers. The generator is driven
from the engine by V-belts. A tensioning device automatically ensures optimum belt tension.
4.11.1 Operating modes
The compressor works with the normal air delivery regulation and generates electrical power at the
same time.
The generator can work in two modes. These are selected by the mode switch:
■ Automatic start
■ Continuous load
Generator main switch
Mode selector switch
What is provided?
OFF
-
Compressed air
ON
Position 1
(automatic start)
Compressed air and electrical power
Position 2
(continuous load)
Electrical power and compressed air
Tab. 60 Generator/compressor operation
Operating mode Automatic start
Continuous load
Switch position Position 1
Position 2
Engine speed
Electrical power takeoff > 100 VA
automatic maximum speed
Permanent maximum speed (en‐
gine under full load)
Power takeoff lass than minimum:
Engine run-on time of approximately 2 minutes
at maximum speed
Advantages
Fuel saving
Constant oscillation between maximum and
minimum speed avoided
Continuous generator power avail‐
able without delay
Tab. 61 Generator operating modes
4.11.2 Operating controls
The switches, fuses and outlet sockets for electrical consumers are located on the generator control
box. Individual consumers are connected only by these outlet sockets.
4
Design and Function
4.11 Generator option
No.: 9_6975 00 E
Service Manual Screw Compressor
M135 SIGMA CONTROL MOBIL
51
