Load Capability [Tbd]; Limit Switch Wiring; Limit Switch Operation - Aerotech ABL9000 Series User Manual

Operating Specifications

3.3. Load Capability [TBD]

3.4. Limit Switch Wiring

ABL/ABLH9000 series stages are provided with a series of optical limit switch assemblies. The limit
switches signal when the stage has reached its maximum useable travel distance in all directions.

3.4.1. Limit Switch Operation

Each limit switch has a light source and detector mounted to a small printed circuit board. Each limit switch
board is mounted at the ends of an axis with their emitter–detector axes perpendicular to the direction of axis
motion. The limit switch itself can be configured as normally closed (NC) or normally open (NO).
If the stage is driven approximately 6 mm beyond the electrical limit, it will encounter a
mechanical stop. Although the operating speed of the stage may be relatively slow, damage
to the stage could result.
3.4.2. Limit Switch Wiring
Limit switches are open-collector, TTL–compatible, electro–optical devices powered by 5 Volts that change
output states when the stage approaches its maximum travel distance and breaks the light beam. Since they
are open-collector devices, they may be interfaced to 24Volt logic inputs. Each limit switch is mounted on a
small printed circuit board. Standard ABL/ABLH9000 Stages include limit switch wiring integrated into the
feedback connector.
Assuming a NC limit configuration, the input to the controller is seen as a logic 0 (typical 0.4V @ 12.8mA)
when no limit condition is present. When the limit switch is activated, a 5V source through a pull-up resistor
causes a logic 1 (typically 4.8-5V) to be seen by the controller input. The limit switch operation for a NO limit
configuration is the exact opposite as described above. See Figure 3-2 for a diagram of limit switch wiring.
Figure 3-2:
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ABL/ABLH9000 Series Stage User's Manual
Normally Closed (NC) and Normally Open (NO) Limit Switch Wiring
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