Fail-safe inductive sensors
May 1st 2008 ifm electronic has introduced
more inductive sensors that
achieve Safety Integrity Level (SIL)
2 or 3.
Available in M12 (SIL2) or M18,
M30 and cube styles (SIL3), the
proximity sensors have two output
signal switching devices (OSSDs)
built in and the new fail-safe series
will work with conventional safety
relays as well as with safety PLCs.
Special demands such as
shielding, twisted
wires or separate
laying are not
placed on the
industrial standard
M123 connection;
the sensor is simply
connected to
existing evaluation
units, safety
controllers and safe
bus systems using
a common
unscreened 4-core
cable.
Aspects such as coil damage,
component health, crossmonitoring
and short circuit
protection are all continuously
checked within the device itself.
Any fault, at any time, is instantly
signalled.
Fail-safe inductive switches from
ifm electronic are constructed with
full redundant and diverse internal
circuits, certified by the TÜV
Rhineland, but retain the
advantages offered by an inductive
sensor.
Some may think that an
inductive sensor that needs no
special target would be easy to
defeat, but that would defeat the
object. The target may be nothing
special, but its position in the right
place at the right
time is what counts.
When the target is
present, any piece
of metal between
the switch and the
target will cause the
output to switch off.
Setting the unit is
not difficult; LEDs
help in adjustment,
while incorporating
a delay to befuddle
the fiddlers.
The company
supplies one of the widest ranges
of sensors for position and process
control, complemented by a large
selection of connection
possibilities, from connecting cable
to AS-interface systems. More articles from ifm electronic Limited: | 
