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VFR4000-OMH0003-D
Design / Selection
3.Solenoid valve drive for AC with a solid state output
(SSR, TRIAC output, etc.)
1) Current leakage
When using a snubber circuit (C-R element) for surge
protection of the output, a very small amount of electrical
current will continue to flow even during the OFF state.
This results in the valve not returning. In a situation where the
tolerance is exceeded, as in the above case, take measures to
install a bleeder resistor.
2) Minimum allowable load amount (Min. load current)
When the consumption current of a valve is less than the
output’s minimum allowable load volume or the margin is small,
the output may not switch normally. Please contact SMC.
4.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.
5. Operation in low temperature conditions
It is possible to operate a valve in extreme temperatures, as low
as
–10°C. Take appropriate measures to avoid the freezing of
drainage, moisture, etc., in low temperatures.
6. Operation for air blowing
When using a solenoid valve for air blowing, use an external
pilot type. Use caution because the pressure drop caused by
the air blowing can have an effect on the internal pilot type
valve when internal pilot type valves and external pilot type
valves are used on the same manifold. Additionally, when
compressed air within the pressure range of the established
specifications is supplied to the external pilot type valve’s port,
and a double solenoid valve is used for air blowing, the
solenoids should be energized when air is being blown.
7. Mounting orientation
Mounting orientation is free.
8. Initial lubrication of main valve
The following initial lubricant has already been applied to the
main valve.
●
Rubber seal, spool valve: Grease
Please consult with SMC, as there are some standard valve
products that use fluorine grease for food processing
equipment (NSF H-1).
9. For the pilot EXH (PE) port
If the solenoid valve and the manifold’s pilot EXH (PE) port is
restricted extremely or blocked, abnormal operation of the
solenoid valve may occur.
Mounting
1. Operation manual
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.
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 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. Refer to the Fittings and Tubing Precautions (Best
Pneumatics No.7) for handling One-touch fittings.
2. 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.
3. 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.
4. Using closed center
For closed center,
check the piping to prevent
air leakage from the piping
between the valve and the cylinder.
Caution
Warning
VFR4000 Series
5 Port Solenoid Valve / Precautions 2
Be sure to read before handling.
Caution
Summary of Contents for VFR4000 Series
Page 1: ...Doc No VFR4000 OMH0003 D PRODUCT NAME 5 Port Solenoid Valve MODEL Series VFR4000 Series...
Page 13: ...12 VFR4000 OMH0003 D VFR4000 Series Construction Be sure to read this before handling...
Page 14: ...13 VFR4000 OMH0003 D VFR4000 Series Construction Be sure to read this before handling...