SLQ-QT500 Datasheet, PDF (4/7 Pages) List of Unclassifed Manufacturers – High Purity Flow Meter

4 Fluidic Connection
Table 4: Fluidic specifications and pressure rating
Parameter
Wetted materials:
 Internal sensor tube material
 Connection tube
Fluidic connection
Pressure drop (at 120 ml/min, IPA, 23°C)
Total internal volume
SLQ-QT500
Quartz
PFA
PFA tube, 6.35 mm (1/4”) OD, 4.35 mm ID
< 2 mbar
5 ml
The flow meter has been robustly engineered to
ensure the internal PFA to Quartz interface provides a
dependable seal without using any additional
adhesives or gasket sealing materials. This tightly
integrated design prohibits any disassembly without
damaging internal components; never disassemble
the flow meter or attempt to replace PFA tubing!
Shortening tubing by cutting to the desired length is
possible. Please consider the following basic
guidelines.
Important note: Make sure to always leave tubing of
sufficient length (depending on the selected type of
fitting) before cutting the tube. Cutting the PFA tubing
too short will require replacing the flow meter!
Basic guidelines:
 PFA tubing is non-replaceable.
 Use tubing adapters for 6.35 mm (1/4 inch)
outer-diameter and 4.35 mm inner-diameter PFA
tubing.
 For optimum accuracy, it is recommended to
leave the tubing on the inlet at its original length,
and to keep it straight. This is most important for
low viscosity liquids at high flow rates. See table
5 for more details.
 On the outlet side, the tubing can be cut or bent
as needed, without affecting the flow meter’s
accuracy for flow in the positive direction
(normal requirements for handling PFA tubing
apply).
 Bending of tubing and mounting orientation has
no influence on the repeatability of the flow
meter. To maintain the same measurement
conditions and benefit from the excellent
repeatability of the SLQ-QT500, the position and
orientation of the flow meter and its connection
tubing should be fixed after installation.
 If the PFA tubing is cut, it must be ensured that
sufficient length is left to connect the flow meter
to your system.
Table 5: Recommended minimum length of straight inlet tube depending on viscosity and flow rate
Flow rate (µl/s)
1000
1500
2000
1.0 (H2O at 23°C)
6 cm
9 cm
12 cm
Kinematic viscosity (mm²/s)
2.5 (IPA at 23°C)
3 cm^a
4 cm^a
5 cm
5.0
2 cm^a
2 cm^a
3 cm^a
a _{Important! This table lists the recommended minimum length from a fluidic point of view. A greater length may be required depending on the}
selected type of fluidic connector.
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Version 3 – October 2014
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