- Xevo TQ-S micro
- Leybold Sogevac SV40 BI F/c pump 960331V3010 version (part number 186006347)
The rotary pump is labeled as shown below, but due to individual differences, the position directly above does not always mean “open”.
Turn the gas ballast valve and the position at where you can hear an air leak sound should be the “open” position.
For more information regarding Ballasting the roughing pump, refer to the appropriate operator's guide: