Error message "Turbo controller fault" seen on vented Xevo TQ-S micro / SQD2 / TQD- WKB4976

SYMPTOMS

• The mass spectrometer vents unexpectedly or does not pump down
• The message "Turbo controller fault" is seen in the MS console

ENVIRONMENT

• Xevo TQ-S micro
• SQD2
• Xevo TQD

CAUSE

Vacuum leak in the turbo pump backing line

or

Roughing pump not switched on

FIX or WORKAROUND

1. Remake the turbo pump backing line connections, paying particular attention to the Legris fittings. Connections at these fittings must not be under strain as this can introduce intermittent leaks. 
2. Ensure that the Legris fitting on the modified vacuum flange is tightly fitted.

ADDITIONAL INFORMATION

The error message "Turbo controller fault" does not necessarily indicate a fault with the turbo controller or turbo pump. It is simply a message from the controller reporting that a reading is outside of a specified range, for example, turbo speed, turbo temperature, or power supply voltage. The most common problem resulting in this message is that the turbo speed is out of specification due to insufficient backing to the turbo pump.