Agilent Technologies 1100 Series, Service Manual, Page: 62 / 288

50 1100 Series Nano Pump Service Manual
2 Troubleshooting and Test Functions
Motor-Drive Power
Motor-Drive Power: Pump channel A
B: Motor-Drive Power: Pump channel B
The current drawn by the pump motor exceeded the maximum limit.
Blockages in the flowpath are usually detected by the pressure sensor in the
damper, which result in the nano pump switching off when the upper pressure
limit is exceeded. If a blockage occurs before the damper (i.e. the pressure
increase cannot be detected by the pressure sensor), the nano pump will
continue to pump. As pressure increases, the pump drive draws more current.
When the current reaches the maximum limit, the nano pump is switched off,
and the error message is generated.
Probable Causes
• Flow path blockage in front of the damper.
• Blocked outlet ball valve.
• High friction (partial mechanical blockage) in the drive assembly.
• Defective drive assembly.
• Defective CSPM board.
Suggested Actions
✔
Ensure the capillaries and frits between the pump head and damper inlet
are free from blockage.
✔
Exchange the outlet ball valve.
✔
Remove the pump head assembly. Ensure there is no mechanical blockage
of the pump head assembly or drive assembly.
✔
Exchange the drive assembly.
✔
Exchange the CSM board.