Festo DNCV Série Notice D'utilisation page 30

DNCV−...
Warning
The piston rod of the DNCV−... moves fast even with a highly restricted setting
(see table below).
S Make sure that the sequence of movement is such that, even after stationary
periods, the following specifications are observed:
The piston of the DNCV−... always moves against a pressurized chamber.
Pressure forces in the direction of outward movement due to piston areas
of different sizes are taken into account..
Type
Situation
in valve
mid−
position
Reaction
Remedy
30
DNCV−...−5/3E−... DNCV−...−5/3B−... DNCV−...−5/2LA−...
Both cylinder Both cylinder
chambers are chambers are
exhausted. pressurized.
When the valve is When the valve is
switched from the switched into the
mid−position the mid−position a force
piston moves arises due to the
against an different piston areas.
unpressurized In the retracted end
chamber. position the piston
rod moves out quickly rod moves out quickly
In valve
inspite of a highly
mid−position the
restriced setting.
piston rod can
move freely.
Always presurize Always actuate the
the mechanical valve mid−position in
position first: the case of the
With retracted extended piston rod.
piston rod
actuate valve
coil 12 first.
With extended
piston rod
actuate valve
coil 14 first.
Cylinder chamber for
extended piston rod is
pressurized
When the valve is
pressurized in the basic
position and with
retracted piston rod, the
piston rod moves out
quickly despite a high
throttle setting.
Press manual override
12 or switch the valve
(pin 6) and pressurize
the DNCV− when the
piston rod is retracted.
Always pressurize the
valve basic position
when the piston rod is
extended.
Festo DNCV−... 0303b English