SMC Networks VP346E Series Operation Manual page 12

When the valve is failing, use this flow chart
Problem to clarify the cause of the failure and take
countermeasures appropriate for the cause.
The valve is slow.
Actuators including cylinder become slow.
Response
failure
Valve and
actuator
become
slow.
Find and check the air leakage point.
1. Air leakage from OUT.
[2(A)] port or EXH. [3(R)] port.
Air leakage
2. Air leakage from the vent
port.
If the countermeasures above are not effective, there may be a problem with the valve.
Stop using the valve immediately.
If any of the examples below are applicable, there may be an internal problem with the valve. Stop using the valve immediately.
1. The voltage used was not the rated voltage.
2. The oil supplied was not the specified type.
3. Lubrication was stopped during operation. Or, lubrication was interrupted temporarily.
4. The product was directly exposed to water with the valve cover, connector block or SI unit removed.
5. Severe impact was applied.
6. Foreign matter such as condensate or dust has entered the product
7. Other than those specified, if precautions on the operation manual apply.
 If the product has failed, then please return the valve without any modifications.
Possible cause
1) Leakage current
When the valve is turned off, it became slow
due to the residual voltage.
2) Clogging of the filter and silencer
Filter or silencer is clogged, or vent port is
blocked.
3) Operation failure or sticking of the main
valve.
Foreign matter from the piping and air source
got caught in the main valve of the valve,
causing a delay.
Malfunction occurred due to sticking such as
swelling of the rubber part of the main valve.
1) Internal air leakage increased because
foreign matter get caught in the main
valve.
2) Sealing failure of the actuator (cylinder)
1) Foreign matter is caught in the pilot
valve armature.
2) Foreign matter caught in the valve seat
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Countermeasures
Check the residual voltage.
Keep the residual voltage at 3% of the rated
voltage (DC coil) or less.
- Replace the filter.
- Replace the silencer.
- Do not block the valve vent port.
- Replace the valve.
- Check for abnormalities in devices other
than valves.
- Clean the air supply.
- If incorrect oil has been used for lubrication,
remove the oil by air blow.
- If there is a large amount of condensate,
install an auto drain or a dryer.
- Replace the valve.
- Clean the air supply.
- Refer to the operation manual of the actuator
for details.
- Replace the valve.
- Clean the air supply.
- Replace the valve.
- Clean the air supply.
No.VP500-OMZ0005-B