Cognex 3D-A5000 Series, Hardware Reference Manual

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To configure the acquisition trigger as a sourcing input, connect the terminal to the high-voltage reference
(24VDC) and the TRIGGER- terminal to the output of the photo-electric sensor.
Trigger (Source)
To configure the acquisition trigger as a sinking input, connect the TRIGGER- terminal to the low voltage reference
(ground) and the terminal to the output of the photo-detector or PLC.
Trigger (Sink)
Be aware of the following I/O line behavior during acquisition:
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The sensor asserts the READY line to indicate that it will perform a hardware-triggered acquisition when it detects
a rising edge on the TRIGGER_IN line.
The sensor must be configured for hardware triggers, an acquisition start command received, and the sensor
must not be currently performing an acquisition.
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The sensor generates a 5.2 ms pulse on the TRIGGER_OUT line at the start of any acquisition sequence
(hardware trigger or software trigger)
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The sensor generates a 5.2 ms pulse on the MISSED_TRIGGER line if it detects a TRIGGER_IN signal but the
READY line is not asserted
Discrete Outputs
See the topic Hardware Triggers on page 13 for details on the acquisition trigger. Your 3D-A5000 sensor supports three
other optically-isolated high-speed outputs that can be used as either NPN (current sinking) or PNP (current sourcing)
lines.
Specification Description
Voltage 26.4VDC maximum through external load
Current 50mA maximum sink current
OFF state leakage current 100µA
External load resistance 240 Ohms to 10K Ohms
Each line rated at a maximum 50mA, protected against over-current, short circuits and transients
from switching inductive loads. High current inductive loads require an external protection diode.
Delay
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10µs (maximum due to opto-isolators turning on)
See the topic I/O Cable on page 13 for the pin assignments of the 3D-A5000 sensor I/O cable.
Your 3D-A5000 sensor uses an identical circuit for all the outputs the 3D sensor supports:
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I/O Cable