Cognex In-Sight 1450, Installation And Reference Manual

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Specifications
3.2 Acquisition Trigger Input
The I/O Expansion Module provides access to the supported vision sensor’s high-speed,
opto-isolated acquisition trigger input. Unlike the general-purpose inputs, the acquisition trigger
input is wired directly to the CCD imager circuitry, bypassing the sensor’s operating system. The
I/O Expansion Module’s micro-controller also monitors the acquisition trigger input.
Table 3-2: Acquisition Trigger Input Specifications
SPECIFICATION DESCRIPTION
ON 20 to 28V (24V nominal) VOLTAGE
OFF 0 to 3V (12V nominal threshold)
ON 10 to 14.4mA
OFF <300 µ A
CURRENT
Resistance ~2K Ohms
DELAY 250 µ Sec latency between leading edge of trigger and start of acquisition. Input pulse should
be a minimum of 1 ms wide.
CAUTION The In-Sight 1450 I/O Expansion 24V OUT pins are intended to supply low current in
support of the I/O lines. Do not use these pins to supply power to other devices.
NOTE Although the Trigger opto-coupler in the I/O module is a bi-directional device, the polarity of the TRG+ and
TRG- terminals should be observed to enable the TRG LED. If polarity is reversed, the LED will not light,
but the camera will still trigger.
To trigger from an NPN (pull-down) type photo-detector or PLC output, connect pin 4 (TRG+) on
the I/O Expansion Module’s terminal block to +24V OUT and connect pin 3 (TRG-) to the output
of the detector. When the output turns ON, it pulls TRG- down to 0V, energizing the In-Sight
camera trigger.
Figure 3-1: Acquisition Trigger Input (NPN Source)
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