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Chapter 3
3.3 Digital I/O Connections
3.3.1 Dry Contact Support for Digital Input
Each digital input channel accepts either dry contact or 0 ~ 5 VDC wet
contact inputs. Dry contact capability allows the channel to respond to
changes in external circuitry (e.g., the closing of a switch in the external
circuitry) when no voltage is present in the external circuit. Figure 3-3
shows external circuitry with both wet and dry contact components, con-
nected as an input source to one of the card's digital input channels.
Figure 3.3: Digital Input Connections
Summary of Contents for 48/24-Channel Digital Input/Output USB Module USB-4751/4751L
Page 1: ...USB 4751 4751L 48 24 Channel Digital Input Output USB Module User Manual...
Page 6: ...USB 4751 4751L User Manual vi...
Page 7: ...2 CHAPTER 1 Introduction Sections include Hardware Features Software Overview...
Page 10: ...USB 4751 4751L User Manual 4...
Page 23: ...2 APPENDIX A Specifications...