Datasheet

Caution
Flow rate
Do not use the product
in this area.
Excess flow area
Output frequency of Karman vortex
Warning
Design/Selection
Caution
Mounting
1. Apply a wrench only to the metal part of the piping
when installing the flow switch onto the system
piping.
Do not apply the wrench to any part other than the piping
attachment, or the switch may be damaged.
Pay attention so that the wrench does not hit the M8
connector. This will damage the connector.
2. Avoid piping in which the piping size of the IN side
of the switch changes suddenly.
When abruptly reducing the size of piping or when there is a
restrictor such as a valve on the IN side, the pressure
distribution in the piping changes and makes accurate
measurement impossible. Therefore, flow restriction measures
such as these should be implemented on the OUT side of the
switch.
Also, leaving the OUT side open or bringing about excessive
flow volume will increase the risk of cavitation and may make
accurate measurement impossible. Increasing the fluid
pressure is one means of reducing cavitation. Try a procedure
such as mounting a restrictor on the OUT side of the switch.
Ensure that there is no malfunction before usage. If the orifice
of the OUT side is fully closed to operate the pump, the switch
may malfunction due to the effect of the pulsation (pressure
fluctuation). Ensure that there is no malfunction before usage.
1. When running high temperature fluid, the product
will also become hot. Avoid touching the product
directly as this may cause a burn.
2.
The product is a flow meter using Karman vortex. The
flow meter using Karman vortex has lower output
frequency at excess flow state. Do not use the product
within the excess flow area in the chart below.
Handling
Warning
1. When adjusting the flow rate with the flow adjust-
ment valve, do not apply excessive force to rotate
it.
Otherwise, this can damage the valve mechanism.
2. When fixing the valve of the flow adjustment valve,
do not apply excessive force to rotate the lock ring.
Otherwise, this can damage the valve mechanism.
3. After adjusting the flow rate, confirm that there is
no water leakage.
After adjusting the flow rate, water leakage may occur due to
the stability of the seal in the valve.
If water leakage occurs, open and close the valve several
times to readjust it, and confirm that there is no water leakage.
4. The flow adjustment valve of this product is not
suitable for applications which require constant
adjustment of flow rate.
Fluid leakage may be generated when the internal seal
reaches the end of its life due to wearing. Therefore, take
measures to protect peripheral equipment, ensure mainte-
nance space and pay attention to the piping design.
5. The flow adjustment valve of this product is not
suitable for applications which require reducing the
flow rate to zero completely. If it is necessary to
reduce the flow rate to zero completely, separately
install a stop valve, etc.
6. Do not lift it by gripping the knob of the flow adjust-
ment valve. Hold the body when handling to avoid
damaging the product.
7. If running high temperature fluid, the flow adjust-
ment valve will also become hot, which leads to a
burn. Therefore, use the flow adjustment valve with
special care.
Handling of Flow Adjustment Valve
Caution
Caution
1. Use the following UL approved products for DC
power supply combinations.
A circuit (class 2 circuit) with maximum 30 Vrms (42.4 V peak)
or less, and a power supply consisting of a class 2 power
supply unit confirming to UL1310, or a class 2 transformer
confirming to UL1585.
1. Since the type of fluid varies depending on the
product, be sure to verify the specifications.
The switches do not have an explosion proof rating. To
prevent a possible fire hazard, do not use with flammable
gases or fluids.
2. Design the system so that the fluid always fills the
detection passage.
Especially for vertical mounting, introduce the fluid from the
bottom to the top. If the flow goes downwards, air bubbles in
the fluid will not be able to get out, causing malfunction.
(There should not be a problem as long as the fluid passage is
completely filled with water.)
Series
PF3W
Specific Product Precautions 1
Be sure to read before handling.
Refer to back cover for Safety Instructions, “Handling Precautions for SMC Products”
(M-E03-3) and the Operation Manual for Flow Switch Precautions. Please download it
via our website. http://www.smcworld.com
Operating Environment
Warning
PVC Piping
Caution
1. Check regulators and flow adjustment valves
before introducing the fluid.
If pressure or flow rate beyond the specified range are applied
to the switch, the sensor unit may be damaged.
2. The fluids applicable for the switch are water and
ethylene glycol aqueous solution (with viscosity of
3 mPa·s [3 cP] or less).
3. Install a filter on the IN side when there is a possi-
bility of foreign matter being mixed with the fluid.
If foreign matter adheres to the switch’s vortex generator or
vortex counter, accurate measurement will no longer be
possible. We recommend a filter with filtration of approx. 40
mesh.
1. After the power is turned on, the switch’s output
remains off while a message is displayed (for
approx. 3 seconds). Therefore, start the measure-
ment after a value is displayed.
2. Perform settings after stopping control systems.
3. Do not apply excessive rotational force to the moni-
tor unit.
The monitor of the integrated display type is rotatable. It can
rotate by 90° counterclockwise and 225° clockwise, in
increments of 45°. The stopper may be damaged if the
monitor unit is turned with excessive force.
1. Never use in the presence of explosive gases.
The switches do not have an explosion proof rating. Never use
in the presence of an explosive gas as this may cause a
serious explosion.
2. Use the switch within the specified fluid and ambi-
ent temperature range.
The fluid temperature range is 0 to 90°C and ambient
temperature range is 0 to 50°C. Take measures to prevent the
fluid from freezing, since this may damage the switch and lead
to a malfunction. Never use the switch in an environment
where there are drastic temperature changes even when
these temperatures are within the specification.
3. If the temperature of the fluid is lower than the
ambient temperature, condensation will be gener-
ated which may damage the product or cause
malfunction.
Do not install the product upside down or vertically. Water
droplets may cause damage earlier.
1. PVC fitting (union)
The PVC fitting (union) must be mounted and joined by an
engineer with sufficient knowledge.
Be sure to confirm that there is no leakage from the fitting after
mounting and joining. If it is mounted and joined by a person
who does not have sufficient knowledge and skills, it may lead
to failure such as leakage.
2. When selecting adhesive for the PVC fitting (union),
confirm that its heat resistance and endurance are
compatible with the operating temperature of the
fluids used. Otherwise, this may cause leakage and
damage.
3. Do not apply excessive force to the PVC piping.
This may cause damage.
4. When the PVC piping type is used, the higher the
fluid temperature, the lower the proof pressure will
be. Therefore, adjust the water hammer pressure
carefully so that it does not exceed the proof pres
-
sure.
1. Take precautions when using the switch for an
interlock circuit.
When a pressure switch is used for the interlock circuit, devise
a multiple interlock system to prevent trouble or malfunction,
and verify the operation of the switch and interlock function on
a regular basis.
Maintenance
Warning
End stop
position
225°
0°
90°
Others
Measured Fluid
Warning
Warning
Series
PF3W
Specific Product Precautions 2
Be sure to read before handling.
Refer to back cover for Safety Instructions, “Handling Precautions for SMC Products”
(M-E03-3) and the Operation Manual for Flow Switch Precautions. Please download it
via our website. http://www.smcworld.com
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