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DICTATOR Technik GmbH · +49 (0)821 246730 · [email protected] · www.dictator.de · 22.06.22
Technical manual: SQUARE 940-2
Reference limit
switch connection
4.11 REFERENCE LIMIT
When using an incremental rotary encoder, it is necessary to use a reference switch/mechan-
ical limit stop, as the door controller cannot detect where the door is when it is switched on.
Therefore, the controller first searches for the reference position (position value 0). This reference
run is performed at slow speed until the door activates the reference position.
If a reference switch is used, please note that the reference switch contact may only change
once during the entire travel of the door. If the reference switch is mounted in the open position,
a normally open contact must be used. If the reference switch is mounted in the closed position
of the door, a normally closed contact must be used. This means that the controller always de-
tects the direction in which it must move in order to reach the reference point.
You set up the correct function for the desired reference under
Set System Setup › Reference
.
