SMC Networks IL201 Series, Operation Manual

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1. Summary
When accidents of air source and piping in pneumatic process control line cause supplying air
failure such as dropping setting pressure, lock-up valve shuts pneumatic circuit between air
source and operating part.
2. Specification
Signal pressure Max. 1MPa (Note 1)
Setting pressure range 0.14
～
0.7MPa (Note 1)
Line pressure Max. 0.7MPa
Effective orifice (Cv factor) 17mm
2
(0.9)
Ambient and fluid temperature
－
5
～
60
℃
Port size Rc 1/4
Differential 0.01 MPa
Mass
IL201 : 450g
IL211 : 640g
(Note 1) Signal pressure and the set pressure must be different for more than 0.1 MPa.
Inadequate differential pressure may increase the bleed amount from the bleed hole
because of the wearing of internal part. This may effect on the performance.
3. Operating principles
When signal pressure entering the upper diaphragm chamber is larger than the force by
pressing adjusting spring, the diaphragm A moves upward, the exhaust valve is closed, signal
pressure enters the lower diaphragm camber, the diaphragm B is a affected, the valve is opened
against the spring, and the flow can go from IN to OUT. When signal pressure is lower than the
setting pressure, the diaphragm is pushed down and the pressure of lower pressure diaphragm
is exhausted from the exhaust valve. Therefore, the valve is closed by spring force and air circuit
is shut down. For single operating type the valve is single seat, and double seat for double
acting.
-3-
Caution