Rockwell Automation 1747-L5xx SLC 500 Modular Hardware Style User Manual - Manual (Page 111)

111 Publication 1747-UM011G-EN-P - June 2008
Chapter
7
Wiring Your I/O Modules
This chapter describes how to wire your I/O modules. It covers the
following:
• Defining sinking and sourcing
• Preparing your wiring layout
• Features of an I/O module
• Recommendations for wiring I/O devices
• Wiring your I/O modules
• Octal label kit installation
• Using removable terminal blocks
Defining Sinking and
Sourcing Sinking and sourcing are terms used to describe a current signal flow
relationship between field input and output devices in a control
system and their power supply.
• Field devices connected to the positive side (+V) of the field
power supply are sourcing field devices.
• Field devices connected to the negative side (dc Common) of
the field power supply are called sinking field devices.
To maintain electrical compatibility between field devices and the
programmable controller system, this definition is extended to the
input/output circuits on the discrete I/O modules.
• Sourcing I/O circuits supply (source) current to sinking field
devices.
• Sinking I/O circuits receive (sink) current from sourcing field
devices.
Europe: dc sinking input and sourcing output module circuits are the
commonly used options.