Festo DGE ZR-RF Series, Руководство по эксплуатации

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DGE−...−ZR−RF
Festo DGE−...−ZR−RF 0405a English
40
Fittin g e x tern a l acc e ss orie s
S
Check whether the scanning variants 1 to 3 in the following table are required
for your application.
S ca n
nin g v a
ri a nt s
1. The
c ontroller req u ire s
a s ep a r a te re f eren c e
point
2. The
c ontroller
d oe s not req u ire a
s ep a r a te re f eren c e
point
A dd ition a l to 1. a n d
2. (irrespective of the
controller type)
Necessity
of
scanning
elements 1 reference point switch
2 hardware limit switches Only 2 hardware
limit switches Always 2 safety limit
switches
Mounting
requireme
nts The ref. point switch must
overlap a hardware limit
switch. The hardware limit
switches must overlap the
safety limit switches. Hardware limit
switch as reference
point switch over
lapping a safety
limit switch With safety distance
from mechanical end
position
Fig.25
S
Use scanning elements with the following features:
D e s i g n P u rpo s e Rem a rk
Safety
limit
switch Mechanical
roller switch
with switching
function:
normally−closed Implementing the
EMERGENCY STOP
function In accordance with
accident prevention
regulations
Will only prevent
consequent damage in
the case of programming
faults
Hardware
limit
switch Switching
function:
normally−closed Implementing
maximum braking
(emergency ramp) Still enables damage−free
braking in the case of
programming faults
Software
limit
switches Limiting of the
positioning range by
programming in the
controller Are not usually overrun
Reference
point
switch Switching
function:
normally−open Definition of a
reference point for the
DGE−...−ZR−RF Regular checks of the
position are recommended
Fig.26