Festo SDAT-MHS - Cylinder Switch Function; Hysteresis Comparator; Normally Open (NO) and Normally Closed (NC) Contacts

SDAT-MHS
Festo – SDAT-MHS – 2017-11f English 9
2.2.2 Cylinder switch function
OUT
IN
1
Switching travel
hysteresis
1 Teach point
Fig. 5 Cylinder switch function
The cylinder switch function consists of the switching travel and hysteresis. Hysteresis serves to sup
press switching signals in the event of fluctuations around the switching point.
– The teach value is the middle of the switching travel.
– Switching travel and hysteresis are not adjustable. For switching travel and hysteresis, values are
stored that correspond to a typical electronic cylinder switch in a typical drive.
2.2.3 Hysteresis comparator
OUT
IN
1
2
Switching travel
1 Teach point 1
2 Teach point 2
Fig. 6 Hysteresis comparator
The teach points (1,2) are linked to the hysteresis comparator function.
– Teach point 1 (ON) is the switch-on point, teach point 2 (OFF) is the reset point.
– Teach point 2 establishes the size of the hysteresis.
2.2.4 Normally open (NO) and normally closed (NC) contacts
The switching logic normally open (NO) is set as standard. The function of the switching output is inver
ted through selection of the normally closed function (NC).