Operation
49
130000761_002_A0 - 08/2008 - © Oerlikon Leybold Vacuum
3.4
Switching on
Switch on the 24 V DC power supply. The yellow LED at the frequency con-
verter lights up.
The maximum starting pressure for the turbomolecular pump can be read
from the graph in Fig. 3.5.
Switch on the turbomolecular pump at the frequency converter
■
via pins 7 and 8 of the socket REMOTE (X1) (see Fig. 2.19) (For example
via a remote control or with the aid of the plug with integrated ON/OFF
switch: see Section 1.5 Accessories).
■
by a start command via the interface; see Section 3.3.
■
For the power supply units offered or recommended by Oerlikon Leybold
Vacuum: If the contacts 7 and 8 at the REMOTE (X1) connector are
closed the pump starts automatically when the DC voltage is switched on
(provided parameter 12 is set to 0).
The turbomolecular pump accelerates. The green LED flashes. When the
pump reaches normal operation the green LED lights up permanently.
Avoid the influences of shock and vibration when the pump is running.
Exposure of the pump to accelerating forces must be avoided or reduced
to such an extent that the rotor unit will not be excited by vibrations. In
the case of critical applications you must consult our Applications Dept.
first.
Caution
Starting pressure
10
3
10
2
10
1
10
0
mbar
0
25
50
75
100
h
-1
125
Sv = Pumping speed of the
forevacuum pump (m
3
·h
-1
)
V = Volume of the vacuum
chamber (m
3
)
Sv / V
S
ta
rt
in
g
pr
es
su
re
Fig. 3.5 Determining the starting pressure of a turbomolecular pump when evacuating large volumes
