6
Troubleshooting
Diagnostic Tests
110
Accela 600 and 1250 Pump Hardware Manual
Thermo Scientific
Testing the Flow Rate
Run this test to compare the actual flow rate with the set flow rate.
To measure the actual flow rate
1. Connect a 40 bar (~580 psi) restrictor cartridge to the LDA outlet. Align the restrictor so
that the flow is in the direction of the arrow marked on the restrictor (see
Figure 108.
LDA attached to a restrictor
2. Fill a mobile phase reservoir with HPLC-grade methanol and connect it to inlet
channel A.
3. Use the instrument control system to set channel A to 100%.
4. Set the flow rate to 1 mL/min.
5. Do one of the following:
• Connect the other end of the restrictor cartridge to an instrument that measures
flow rate.
–or–
• Connect the other end of the restrictor cartridge to a length of tubing and place the
tubing into an empty, 10 mL graduated cylinder.
6. Start the pump, wait 2 minutes, and then stop the pump.
7. If you do not have a flow rate meter, measure the fluid in the graduated cylinder. The
actual flow rate equals the measured volume divided by two.
8. Compare the actual flow rate with the set flow rate. Under these conditions, the accuracy
of the flow should be ±0.5%.
LDA outlet
Restrictor cartridge
