Rockwell Automation 1746-NR4 SLC RTD/Resistance Input Module User Manual - Manual (Page 63)

63 Publication 1746-UM008B-EN-P - December 2006
Chapter
5
Channel Configuration, Data, and Status
This chapter examines the channel configuration word and the
channel status word bit by bit. It explains how the module uses
configuration data and generates status during operation. It gives you
information about how to:
• configure a channel.
• examine channel input data.
• check a channel’s status.
Channel Configuration The channel configuration word is a part of the RTD module’s output
image. Output words 0…3 correspond to channels 0…3 on the
module. Setting the condition of bits 0…15 in these words via your
ladder logic program causes the channel to operate as you choose (for
example, RTD type or reading in °C). Output words 4…7 are used to
further define the channel configuration to let you choose a scaling
format other than the module default when using the proportional
counts data format. You can use words 4 and 5 to define one user-set
range and words 6 and 7 to define a second range.
A bit-by-bit examination of the configuration word is provided in the
Channel Configuration Word (O:e.0 through O:e.3) - Bit Definitions
table on page 66. Programming is discussed in chapter 6. Addressing
is explained in chapter 4.
Module Output Image (Configuration Word)
CH 0 Configuration Word
0 15
0 15
0 15
0 15
O:e.0
O:e.1
O:e.2
O:e.3
CH 1 Configuration Word
CH 2 Configuration Word
CH 3 Configuration Word
Defines user±set lower scale limit for range 0
0 15
0 15
0 15
0 15
O:e.4
O:e.5
O:e.6
O:e.7
Defines user±set upper scale limit for range 0
Defines user±set lower scale limit for range 1
Defines user±set upper scale limit for range 1