Solvent Selection Valve And Solvent Lines - Fluid Path Test - LC Packings SWITCHOS II User Manual

5.2.3 Solvent Selection Valve and Solvent Lines – Fluid Path Test
To determine if the fluidic path for solvent line is operating properly and if the
resistance of the flow path is within the specifications:
a) Fill each solvent bottle (with methanol) until the fluid level corresponds to the
top of the Switchos housing.
b) Open the four He shut-off valves on the bottle cap assemblies to open the
solvent lines (the He supply line has to be shut off for this test).
c) The four solvent lines should be well flushed using the Purge function of the
loading pump. If is not possible to flush the lines, check for clogged or dirty
solvent filters (sparging/filter frits) or bent solvent lines.
d) Switch the flow delivery of the loading pump off, disconnect the solvent inlet
line from the pump head and connect a 250 µL syringe (i.e. the plunger
should be removed) using an adapter (P/N 160259) as shown in FIGURE 5-2.
FIGURE 5-2. Placing the Syringe on the Solvent Inlet Line
e) Select solvent channel A by the SSV button on the rear of the Switchos. The
LED corresponding to Valve A should be illuminated.
f) Measure the flow rate from the inlet tubing for one minute. The flow rate
should be greater than 50 µL/min for a solvent line that is functioning
properly.
g) Repeat steps (e) and (f) for each solvent line.
Note: If the flow is less than the specified value, repeat the test with the solvent
filters removed. If the flow is within specifications after the filters have been
removed, they are clogged, dirty or defective and must be replaced.
Note: As an alternative to using a syringe, this test can be performed by allowing
the solvent to drip from the solvent inlet line and counting the number of drops
per minute. At least 5 drops per minute should be observed if the proportioning
valve opens properly. If the flow rate is less than 5 drops/min, repeat the test
with the solvent filters removed. If the flow is within specifications after the
filters have been removed, the filters are clogged, dirty or defective and must be
replaced.
User's Manual Switchos
D850R3
Testing the Switchos
5-3