Chapter 4
Digital I/O Functionality
NI CVS-1450 Series User Manual
4-12
ni.com
Considerations When Connecting the Digital I/O
The isolated trigger inputs on the CVS-1450 device are current sinking
and optically isolated. Figure 4-6 shows the trigger input interface circuit.
Wiring an Isolated Input to a Sourcing Output Device
You can wire an isolated input to a sourcing output device, as shown in the
example in Figure 4-5. Refer to Appendix B,
, for switching
thresholds and current requirements.
Caution
Do
not
apply a voltage greater than 30 VDC to the isolated inputs. Doing so could
damage CVS-1450 device.
Figure 4-5.
Example of Connecting an Isolated Input to a Sourcing Output Device
Wiring an Isolated Output to an External Load
The digital output circuit sources current to external loads, as shown in
the example in Figure 4-6.
Caution
Do
not
draw more than 100 mA from 24 V or 30 V isolated outputs. Do
not
draw
more than 50 mA from 5 V isolated outputs.
Vcc
Sourcing
Output
Device
Viso
Current
Limiter
Ciso
CVS-1450 device
Input
