Channel Configuration - Allen-Bradley SLC 500 1746-NR4 User Manual

Channel Configuration

Channel Configuration, Data, and Status
This chapter examines the channel configuration word and the channel status
word bit by bit, and 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
The channel configuration word is a part of the RTD module's output image
as shown in the figure below. 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, reading in C). Output words 4–7 are used to further
define the channel configuration to allow you to 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 Table 5.A.
Programming is discussed in chapter 6. Addressing is explained in chapter 4.
Figure 5.1
Module Output Image (Configuration Word)
O:e.0
15
O:e.1
15
O:e.2
15
O:e.3
15
O:e.4
15
O:e.5
15
O:e.6
15
O:e.7
15
Module default settings for configuration words 0–7 are all zeros. Scaling
defaults are explained on page 5–14 under the explanation for the User–set
Scaling Select bits 13 and 14.
Chapter
5
CH 0 Configuration Word
CH 1 Configuration Word
CH 2 Configuration Word
CH 3 Configuration Word
Defines user–set lower scale limit for range 0
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
0
0
0
0
0
0
0
0
5–1