Waters ACQUITY UPLC M-Class System Manual page 60

4 Maintaining the system
ACQUITY UPLC M-Class System troubleshooting: (Continued)
Symptom
Missing peaks
(continued)
Negative peaks
60 March 10, 2014, 715003588 Rev. A
Suspected cause
Insufficient trapping
Insufficient initial sample
preparation
Interrupted spray
Bad trap column
Solvent front at the
beginning of the
chromatogram at column
void volume
Signal cables connected
improperly (analog only)
Loss of spray
Possible solution
• Check the inlet method
parameters.
• Establish if the
trapping column is
trapping peptides
efficiently.
Refer to the laboratory
sample preparation
protocol.
The Universal
See also:
NanoFlow Sprayer
Installation and
Maintenance Guide.
Replace the column.
Make the sample diluent
similar to the initial
mobile phase.
Reset signal polarity,
making sure to match
positive and negative
connections. Refer to the
component overview and
maintenance guides on the
documentation CD for
specific signal connection
information.
Troubleshoot the loss of
spray.
The Universal
See also:
NanoFlow Sprayer
Installation and
Maintenance Guide.