Festo MPA-ASI Series, Руководство пользователя

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4. Commissioning
4−5
Festo P.BE−MPA−EN en 0802c
The pilot air must reach a pressure of 3
Ū
8 bar as soon as it
is switched on, Otherwise, there is no guarantee that the
valve will switch directly (see diagram).
If the pressure is less than 3 bar, there may be a delay before
the valve is switched, in spite of an electric signal being pres
ent. The slow increase in pressure of the complete supply
does not then affect the actuator. The actuator would react
suddenly (e.g. a cylinder would extend or retract suddenly,
depending on the valve function).
1
4 2
5 3
14 12
1
2
1
12/14
12/14
3
82/84
2
1
Externally supplied pilot air (3 to 8 bar), branched in
front of the safety start−up valve
2
Safety start−up valve (slow build up of pressure of
complete supply)
Fig.4/1: Example of valve−cylinder combination with slow
increase in pressure of the complete supply