Chapter 1
Overview
1–7
The RTD module communicates to the SLC 500 processor through the
parallel backplane interface and re5V dc and +24V dc power from
the SLC 500 power supply through the backplane. No external power supply
is required. You may install as many RTD modules in your system as the
power supply can support, as shown in Figure 1.3.
Figure 1.3
RTD Configuration
RTD Modules
SLC Processor
Each individual channel on the RTD module can receive input signals from
2, 3 or 4–wire RTD sensors or from resistance input devices. You configure
each channel to accept either input. When configured for RTD input types,
the module converts the RTD readings into linearized, digital temperature
readings in
°
C
or
°
F. When configured for resistance inputs, the module
provides a linear resistance value in ohms.
Important: The RTD module is designed to accept input from RTD sensors
with up to 3 wires. When using 4–wire RTD sensors, one of the
2 lead compensation wires is not used and the 4–wire sensor is
treated like a 3–wire sensor. Lead wire compensation is
provided via the third wire. See NR4 Wiring Considerations on
page vi for more information.
System Overview
Summary of Contents for SLC 500 1746-NR4
Page 1: ...User Manual SLC 500t RTD Resistance Input Module Cat No 1746 NR4 Allen Bradley AB Spares ...
Page 15: ...Preface P 8 Notes AB Spares ...
Page 37: ...Chapter 2 Quick Start 2 12 Notes AB Spares ...
Page 63: ...Chapter 4 Preliminary Operating Considerations 4 12 Notes AB Spares ...
Page 87: ...Chapter 5 Channel Configuration Data and Status 5 24 Notes AB Spares ...
Page 107: ...Chapter 7 Module Diagnostics and Troubleshooting 7 8 Notes AB Spares ...
Page 117: ...Chapter 8 Application Examples 8 10 Notes AB Spares ...
Page 123: ...Appendix A Specifications A 6 Notes AB Spares ...
Page 125: ...Appendix B RTD Standards B 2 Notes AB Spares ...
