Festo VOFA-B26-T52-M Series, Руководство по эксплуатации

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Festo VOFA−... 1004NH English
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Switching characteristics
Fig.9 shows the pneumatic and electric switch−on characteristics at the control
block with PNP proximity sensors and without resistive load.
Throughinterrogation (resistive load) of the proximity sensor, the switching times
can be extended by max. 2ms. With use of NPN proximity sensors,
thesignalcharacteristics are reversed, i.e. rising instead of dropping.
Process during switch−on:
At the time t=0, both coils are energised. After approx. 11ms, the proximity
sensors report exit from the neutral position of the solenoid valves, and after a
total of approx. 22ms the pneumatic actuations of port (2) and (4) change.
p2
p4
U2
U1
1
p2 = pressure on port (2)
2
p4 = pressure on port (4)
3
U1 = signal voltage on proximity sensorE1
4
U2 = signal voltage on proximity sensorE2
Fig.9: Path−step diagram with signal sequence during switch−on of the control block
(diagramshowsmeasurements with the PNP proximity switch without resistive load)