SMC Networks SV Series Manual

3/4/5-Port Solenoid Valves
Precautions 1
Be sure to read this before handling products.
Warning
1. Confirm the specifications.
Products represented in this catalog are designed only for use
in compressed air systems (including vacuum).
Do not operate at pressures, temperatures, etc., beyond the
range of specifications, as this can cause damage or malfunc-
tion. (Refer to the specifications.)
Please contact SMC when using a fluid other than
compressed air (including vacuum).
We do not guarantee against any damage if the product is
used outside of the specification range.
2. Actuator drive
When an actuator, such as a cylinder, is to be driven using a
valve, take appropriate measures (such as the installation of a
cover or the restricting of access to the product) to prevent
potential danger caused by actuator operation.
3. Intermediate stops
Rubber seal: Use a closed center type valve.
Metal seal: For the exhaust center type valve, use in combi-
nation with either a double check spacer or a double check
block.
For the 3-position closed center or double check valve
types, it is difficult to make the piston stop at the required
position accurately 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 period of time.
However, as the metal seal closed center type valve leaks
more air than the rubber seal and double check type valves,
the intermediate stopping time will be shorter.
4. Effects of back pressure when using a mani-
fold
Use caution when valves are used on a manifold because
actuators may malfunction due to back pressure.
Especially when using a 3-position exhaust center valve, a
double check valve, or a single acting cylinder, take appropri-
ate measures to prevent malfunction by using it with an
individual EXH spacer assembly, a back pressure check
valve, or an individual exhaust manifold.
Also, since the SQ1000 4-position dual 3-port valve is a 4-port
valve specification (R1 and R2 are common), one back
pressure check valve can be installed. As a result, back
pressure from valves in other stations can be prevented, but
back pressure inside this valve cannot be prevented.
5. Holding 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 suitable for use as an emergency shut-
off valve, etc.
The valves listed in this catalog are not designed for safety
applications such as an emergency shutoff valve. If the valves
are used in such applications, additional safety measures
should be adopted.
7. Release of residual pressure
For maintenance and inspection purposes install a system for
releasing residual pressure. Especially in the case of the
3-position closed center valve or double check valve types,
ensure that the residual pressure between the valve and the
cylinder is released.
3
D
Design/Selection
8. Operation in a vacuum condition
When a valve is used for switching a vacuum, take measures
to install a suction filter or similar to prevent external dust or
other foreign matter from entering inside the valve.
In addition, at the time of vacuum adsorption, be sure to
supply a constant supply of vacuum. Failure to do so may
result in foreign matter sticking to the adsorption pad or air
leakage, causing the workpiece to drop.
9. Regarding vacuum switch valves and vacu-
um release valves
If a non-vacuum valve is installed in the middle of a piping
system that contains a vacuum, the vacuum condition will not
be maintained. Use a valve designed for use under vacuum
conditions.
10. Double solenoid type
When using the double solenoid type for the first time, actua-
tors may travel in an unexpected direction depending on the
switching position of the valve. Implement measures to
prevent any danger from occurring when operating the actua-
tor.
11. Ventilation
Provide ventilation when using a valve in a confined area,
such as in a closed control panel. For example, install a
ventilation opening, etc., in order to prevent pressure from
increasing inside of the confined area and to release the heat
generated by the valve.
12. Extended periods of continuous energization
If a valve will be continuously energized for an extended
period of time, the temperature of the valve will increase due
to the heat generated by the coil assembly. This will likely
adversely affect the performance of the valve and any
nearby peripheral equipment. Therefore, if the valve is to be
energized for periods of longer than 30 minutes at a time or
if during the hours of operation the energized period per day
is longer than the de-energized period, we advise using a
valve with specifications listed below.
• Pilot operated: A 0.4 W or lower valve, such as the SY
series, or a valve with a power-saving circuit
• Direct operated: A continuous duty type valve such as the
VK series or the VT series
If conflicting instructions are given in the "Specific Product
Precautions" or on the "How to Order Valves" page, give
them priority.
13. Do not disassemble the product or make any
modifications, including additional machin-
ing.
Doing so may cause human injury and/or an accident.
14. Resumption after a long period of holding
time
When resuming operation after a long period of holding time,
there are cases in which, regardless of whether the product is
in an ON or OFF state, there is a delay in the initial response
time due to adhesion. Conducting several cycles of running-in
operation will solve this problem. Please consider implement-
ing this before resumption.