SLOW OPERATION FOR MAINTENANCE PURPOSES
132  OI 248 (EN) REV6 /REV3
Locking the Undervoltage Releases
• If the spring mechanism is equipped with undervoltage releases
and if slow closing or opening operations are necessary, then the
undervoltage release must be locked.
If Then
Undervoltage release has no
lokking device
10 Locking device for under-
voltage release 
Insert hook of locking device (10)
and pull out solenoid until it hits
the stop;  
• then hand-tighten the nut
slightly.
Undervoltage release has integ-
rated locking device
• Turn the locking lever from
operation position to locking
position
Locking lever in operation positon
Locking lever in locking positon