User manual

1260 Nanoflow Pump User Manual 111
Test Functions and Calibration
8
Micro Mode Pressure Test
Micro Mode Pressure Test Results
The test results are evaluated automatically. The sum of all leaks within the
column flow path from the EMPV to the blank nut must be lower than
100 nL/min.
If the pressure test fails
Ensure all fittings between the pump and the blank nut are tight and repeat
the pressure test. If the test fails again, insert the blank nut at the outlet of the
previous module in the stack, and repeat the pressure test. Exclude each
module one by one to determine which module is leaky.
Potential Causes of Micro Mode Pressure Test Failure
After isolating and fixing the cause of the leak, repeat the pressure test to
confirm the system is tight.
NOTE
Small leaks, with no visible leaks in the flow path can cause the test to fail.
Tabl e 21 Potential Cause (Pump)
Potential Cause (Pump) Corrective Action
Loose or leaky fitting. Tighten the fitting or exchange the capillary.
High flow sensor offset. Run the flow sensor accuracy calibration and
correct the flow sensor offset.
Tabl e 22 Potential Cause (Autosampler)
Potential Cause (Autosampler) Corrective Action
Loose or leaky fitting. Tighten or exchange the fitting or capillary.
Needle seat. Exchange the needle seat assembly.
Rotor seal (injection valve). Exchange the rotor seal.
Damaged metering seal or piston. Exchange the metering seal. Check the piston
for scratches. Exchange the piston if required.