Sample linearity issue on TQD, Xevo TQ Absolute, Xevo TQ MS, Xevo TQD, Xevo TQ-S, Xevo TQ-S cronos, Xevo TQ-S micro, or Xevo TQ-XS - WKB245107

SYMPTOMS

• Poor linearity with customer's samples
• Setup solution looks fine in both MS1 and MS2 modes
• Low sensitivity on customer´s samples

ENVIRONMENT

• ACQUITY TQD system
• Xevo TQ Absolute 
• Xevo TQ MS
• Xevo TQD
• Xevo TQ-S
• Xevo TQ-S cronos
• Xevo TQ-S micro
• Xevo TQ-XS

CAUSE

Argon gas turned off on the argon cylinder regulator.

FIX or WORKAROUND

Turn on the argon gas and set to the correct pressure (0.75 bar for TQ-XS and 0.5 bar for TQ-S; for other models, refer to the installation manual).

ADDITIONAL INFORMATION

The regulator valve was found to be completely open and the gauge was reading zero. However, software was still showing collision gas readback as expected.