Festo Электроцилиндр - Manual (Page 22)

2 Overview
22 Festo – GDCP-CMMO-ST-EA-SY-EN – 1301a – English
2.7.2 Homing methods to a fixed stop
Homing to a fixed stop is only possible in closed-loop operation ( section 2.2.4).
The stop is detected by a motor shutdown in combination with a sharp rise in the motor current. The
parameters for stop detection can be set in FCT.
Homing methods to the stop
– Negative fixed stop (retracted end position)
REF REF AZ
+
1
2
– Positive fixed stop (extended end position)
AZ
–
REF
REF
1 2
1 Homing: The drive moves to the fixed stop at the search speed (= reference point REF).
2 Movement to zero: the drive moves from the reference point REF to the axis zero point AZ.
Tab. 2.3 Homing to the stop
Note
Material damage due to moved measuring reference system
In the event of greatly reduced dynamic values (low maximum motor current) combined
with high travelling resistance (e.g. due to frictional grip), there is a danger that the
drive will come to a standstill and the controller will recognise a stop incorrectly.
A movement to zero should be executed when homing to a fixed stop ( section 2.7.6)
in order to exit the stop position. Otherwise the drive could be driven continuously
against an elastic stop, which would result in a strong temperature increase and eventu-
ally lead to the controller shutting down.
If the system does not have a stop (axis of rotation), the homing run will never be com-
pleted, i.e. the drive will run continuously at the parameterised search speed.