1. Actuator drive
When an actuator, such as a cylinder, is to be driven using a
valve, take appropriate measures to prevent any potential
danger caused by actuator operation.
2. Intermediate stopping
When a 3-position closed center valve is used to stop a
cylinder's piston at an intermediate position, accurate
stopping of the piston in a predetermined position is not
possible due to the compressibility of air.
Furthermore, since valves and cylinders are not guaranteed
for zero air leakage, it may not be possible to hold a stopped
position for an extended length of time. Contact SMC if it is
necessary to hold a stopped position for an extended time.
3. Effect of back pressure when using a
manifold
Use caution when valves are used on a manifold, as actuator
malfunction due to back pressure may occur. Special caution
is necessary when using a 3-position exhaust center valve, or
when driving a single acting cylinder. In cases where there is
a danger of this kind of malfunction, take countermeasures by
using a back-pressure check valve, an individual EXH spacer
assembly, or an EXH blocking plate.
4. Dealing with pilot exhaust
Operate the pilot exhaust port (PE) with silencers mounted on
both the D and U sides, or with release to atmosphere. If
merged with the main exhaust, the main valve may
malfunction due to back pressure.
5. Holding of pressure (including vacuum)
Since valves are subject to air leakage, they cannot be used
for applications such as holding pressure (including vacuum)
in a pressure vessel.
6. Not for use as an emergency shutoff valve
None of the valves featured in this catalog is designed for
safety applications such as an emergency shutoff valve. If
application to this type of system is required, other reliable
safety assurance measures should also be adopted.
7. Maintenance space
The installation should allow sufficient space for maintenance
activities.
8. Release of residual pressure
Provide a residual pressure release function for maintenance
purposes. Special consideration should be given to the
release of residual pressure between the valve and cylinder
in the case of a 3-position closed center type valve.
9. Vacuum applications
When a valve is used for vacuum switching, take appropriate
measures against the suction of external dust or other
contaminants through vacuum pads and exhaust ports. An
external pilot type valve should be used in such cases.
Contact SMC regarding the use of an internal pilot type or air
operated valve.
10. Take suitable protective measures in
locations or applications where valves are
constantly exposed to water.
Design
Warning
Selection
Warning
Caution
Switching element
OFF
CR
Leakage current
Valve
Power
supply
1. Confirm all specifications.
The products featured in this catalog are designed only for use
in compressed air systems (including vacuum). Do not operate
at pressures or temperatures beyond the range of specifications,
as this can cause damage or malfunction. (Refer to specifica-
tions.)
Contact SMC when using a fluid other than compressed air
(including vacuum).
2. Extended periods of continuous energization
Contact SMC if valves will be continuously energized for
extended periods of time.
1. Momentary energization
If a double solenoid valve will be operated with momentary
energization, it should be energized for at least 0.1 second.
However, depending on the secondary load conditions, it
should be energized until the cylinder reaches the stroke end
position. If the valve is to be used in an air blowing application,
it should be energized continuously during the application.
2. Leakage voltage
When using a C-R element (surge voltage suppressor) for
protection of the switching element, please keep in mind that
leakage voltage will increase due to leakage current flowing
through the C-R element.
Limit the amount of residual leakage voltage to the following
values:
2% or less of rated voltage
3. Low temperature operation
Avoid ambient temperatures outside the range of –10°C to
50°C. At low temperatures, take any necessary steps to avoid
solidification or freezing of drainage and moisture.
4. For air blowing applications
When using solenoid valves for air blowing, use external pilot
type valves.
Also, air supply to the external pilot port should be compressed
air that is within the pressure range prescribed in the
specifications.
5. Mounting orientation
In the case of a single solenoid, the mounting orientation is
unrestricted. In the case of double solenoid or 3-position
valves, mount so that the spool valve is horizontal.
Also, when mounting for an application that will inevitably
involve vibration or impact, mount so that the spool valve is at
a right angle to the direction of vibration.
Do not use in applications where vibration or impact exceed
the product's specifications.
With DC coil
Leakage
voltage
30
5-Port Solenoid Valve Precautions 1
Be sure to read before handling.
Series VQC
To Next Page
Loading...
