DMES
Festo – DMES – 2017-07e English 11
6.3 Installing the external accessories
To protect the end positions against uncontrolled overtravel:
Check whether proximity sensors are necessary (hardware limit switches).
If proximity sensors are used as limit switches:
Use proximity sensors with normally-closed function.
These protect a DMES with a fractured proximity sensor cable from overrunning the end position.
If proximity sensors are used as reference switches:
Use proximity sensors that correspond to the input of the controller being used.
If you are using magnetically-actuated proximity sensors:
Use the slots èFig. 15.
Note that the magnet is situated asymmetrically on the
inner slide (on the side facing away from the motor).
Avoid external influences from magnetic or ferritic parts
in the vicinity of the proximity sensors (minimum dis
tance of 10 mm from the slot nuts).
For DMES-25: Only place proximity sensors in the lateral
slots. The magnetic field in the lower slot is very weak.
For DMES-40: Only place the proximity sensors SMT-8
(high response sensitivity) in the lateral slots. The mag
netic field in the upper slots is very strong (danger of
multiple switchings).
Fig. 15
DMES-25
DMES-18
DMES-40 DMES-63
If you are using inductive proximity sensors:
Use switch lugs, sensor brackets and proximity sensors (è11 Accessories).
Use hammer-head screws for fastening the sensor
supports in the slot.
The T-head bolts require the cut-out on the cylinder bar
rel as a guide opening. You can bring the hammer-head
screw into the holding position by turning it 90°.
Fig. 16
To avoid contamination:
Use cover rails (è11 Accessories) as slot covers in all unused slots.
