3.8
Changing the frequency dependent normal
operation level
Depending on the quality of the vacuum which needs to be
provided by the turbomolecular pump it may make sense
to reduce the frequency dependent normal operation thres-
hold, so that the ready status can be attained faster by the
vacuum system. The factory default of 90 % represents a
good compromise so that a change will hardly ever be
required.
For this proceed as follows:
With the aid of a Windows PC and the PC software
“TURBO. DRIVE Server” change the setting for the parame-
ter 25 “Frequency dependent normal operation level”. The
possible values for parameter 25 can be varied within the
limits of 35 to 99 % of parameter 24 (nominal speed
depends on the type of connected pump).
So as to retain the value saved for parameter 25 when
switching the pump off, the parameter value needs to be
saved permanently. For this enter any value (for example 1)
for parameter 8. Thereafter changed parameters will be
saved permanently.
Operation
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17200492_002_A5 - 04/2011 - © Oerlikon Leybold Vacuum