National Instruments NI 1712 User Manual - page 41
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NI 17xx User Manual
The isolated outputs can be used to drive external loads, as shown in Figures 4-6 and 4-
7
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Figure 4-6.
Connecting an Isolated Output to a Sourcing External Load
Figure 4-7.
Connecting an Isolated Output to a Sinking External Load
Protecting Against Inductive Loads
When an inductive load, such as a relay or solenoid, is connected to an output, a large
counter-electomotive force may occur at switching time due to energy stored in the inductive
load. This flyback voltage can damage the outputs and the power supply.
To limit flyback voltages at the inductive load, install a flyback diode across the load. Mount the
flyback diode as close to the load as possible. Use this protection method if you connect any of
the isolated outputs to an inductive load.
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