Edwards SCU-350 Series

SCU-350 Series Control Unit for Turbomolecular Pump
MT-21E-201-E
Page 30
3
INSTALLATION
3.11 Tuning
3.11.1 Tuning
Tuning is required to align the position of levitation in the STP pump axial direction with the centre of
the rotor's movable range. Tuning can be performed simply by pressing the "RESET" switch on the
front panel (refer to Figure 10).
Tuning is required in the following cases in which the position of levitation may deviate from the centre
of the rotor's movable range:
When purchasing only the SCU-350 and connecting to the STP pump for the first time.
When changing the length of the STP connection cable (not when changing the length of the
power cable).
Connecting a different STP pump to the SCU-350 after the tuning is performed.
3.11.2 Tuning method
Refer to Figure 24.
1. Ensure all cables are connected.
2. Turn "ON" the MAIN POWER on the SCU-350 rear panel.
3. After the STP pump completes the self test and "LEVITATION" is displayed, press the "RESET"
switch on the front panel for approximately 3 seconds.
4. When the LCD displays "TUNING!", release the "RESET" switch. The tuning is performed
automatically.
5. Approximately 1 minute later the LCD displays "TUNING COMPLETE", and then displays
"LEVITATION". This completes the tuning.
Note: Tuning can be performed only while the STP pump is in the LEVITATION state. (It cannot be
performed while the STP pump is in the ACCELERATION, NORMAL OPERATION, or BRAKE
state)
When performing the tuning during remote operation, press the "RESET" switch on the front
panel. (The remote signal cannot be used for tuning)
Once tuning is completed, re-tuning is not required unless the configuration (the STP pump
serial number, the SCU-350 serial number, and the STP connection cable length) is changed.
Although the STP pump produces an abnormal noise during tuning, this is not an indication of
abnormality.