Warning
Design / Selection
3. Surge voltage suppressor
2) If a surge protection circuit contains nonstandard diodes, such
as Zener diodes or varistor, a residual voltage that is in
proportion to the protective circuit and the rated voltage will
remain. Therefore, take into consideration the surge voltage
protection of the controller..
In the case of diodes, the residual voltage is approximately 1 V.
4. Surge voltage intrusion
With non-polar type solenoid valves, at times of sudden
interruption of the loading power supply, such as emergency
shutdown, surge voltage intrusion may be generated from loading
equipment with a large capacity (power consumption), and a
solenoid valve in a de-energized state may switch over (see
Figure 1).
When installing a breaker circuit for the loading power supply,
consider using a solenoid valve with polarity (with polarity
protection diode), or install a surge absorption diode between the
loading equipment COM line and the output equipment COM line
(see Figure 2).
5. Operation in low temperature condition
Take appropriate measures to avoid the freezing of drainage,
moisture, etc. in low temperatures.
- VK300 series can be used down to -5°C.
- VK3000 series can be used down to -10°C.
6. Mounting orientation
Mounting orientation is unrestricted.
7. Initial lubrication of main valve
Initia
l
lubricant has already been applied to the main valve.
Mounting
1. Operation Manual (this document)
Install the products and operate them only after reading the
operation manual carefully and understanding its contents.
Also, keep the manual where it can be referred to as necessary.
2. Ensure sufficient space for maintenance activities.
When installing the products, allow access for maintenance
and inspection.
3. Tighten threads with the proper tightening torque.
When installing the products, follow the listed torque
specifications.
4. If air leakage increases or equipment does not
operate properly, stop operation.
Check mounting conditions when air and power supplies are
connected. Initial function and leakage tests should be
performed after installation.
5. Painting and coating
Warnings or specifications printed on or affixed to the product
should not be erased, removed, or covered up.
Please consult with SMC before applying paint to resinous parts,
as this may have an adverse effect due to the solvent in the paint.
Piping
1. Preparation before piping
Before piping is connected, it should be thoroughly blown out
with air (flushing) or washed to remove chips, cutting oil, and
other debris from inside the pipe.
2. Winding of sealant tape
When screwing piping or fittings
into ports, ensure that chips from
the pipe threads or sealing
material do not enter the piping.
Also, if sealant tape is used,
leave 1 thread ridge exposed at
the end of the threads.
3. Connection of fittings
When screwing fittings into valves, tighten as follows.
(1) Follow the procedures below when installing an SMC fitting, etc.
・
M5 types
After tightening the fitting by hand, use a wrench to tighten
the fitting an additional approximately 1/6 to 1/4 turn. As a
reference value, tightening torque is 1 to 1.5 N
･
m.
Note) If tightened excessively, the thread of the product may
break or the gasket may deform. If tightened insufficiently,
the thread of the product may become loose. In either
case, air leakage can occur.
(2) Follow the procedure of the manufacturer when fittings other
than SMC is used.
Tightening Torque for Piping
Connection thread
Proper tightening torque
(
N
･
m)
Rc1/8
3~ 5
Caution
Caution
VK300/3000 Series
Precautions for 3/5 Port Solenoid Valve 2
①
Be sure to read before handling.
- 5 -
VK300
**
-OMH0002-C
