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No.VP500-OMZ0005
Design/Selection
1. Confirm the specifications.
Products represented in this instruction manual are designed only
for use in compressed air systems. Do not operate at pressures or
temperatures, etc., beyond the range of specifications, as this can
cause damage or malfunction.
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. Holding pressure
Since valves are subject to air leakage, they cannot be used
for applications such as holding pressure in a pressure vessel.
4. Not suitable for use as an emergency shutoff
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.
5. Release of residual pressure
For maintenance and inspection purposes install a system for releasing
residual pressure.
6. 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.
7. Do not disassemble the product or make any
modifications, including additional machining.
Doing so may cause human injury and/or an accident.
8. 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 implementing this before
resumption.
1. Leakage voltage
Take note that the leakage voltage will increase when a resistor is
used in parallel with a switching element or when a C-R circuit
(surge voltage suppressor) is used for protecting a switching device
because of the leakage voltage passing through the C-R circuit.
The suppressor residual leakage voltage should be 3% or less of
rated voltage.
2. Surge voltage suppressor
1) The surge voltage suppressor built into the valve is intended to
protect the output contacts so that the surge generated inside
valve does not adversely affect the output contacts. Therefore, if
an overvoltage or overcurrent is received from an external
peripheral device, the surge voltage protection element inside
the valve is overloaded, causing the element to break. In the
worst case, the breakage causes the electric circuit to enter
short-circuit status. If energizing continues while in this state, a
large current flows. This may cause secondary damage to the
output circuit, external peripheral device, or valve, and may also
cause a fire. So, take appropriate protective measures such as
the installation of an overcurrent protection circuit in the power
supply or a drive circuit to maintain a sufficient level of safety.
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 1V.
3. Surge voltage intrusion
With non-polar type 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 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).
3/4/5-Port Solenoid Valves
Precautions 1
Be sure to read this before handling products.
