Rockwell Automation 1746-NR4 SLC RTD/Resistance Input Module User Manual - Manual (Page 64)

Publication 1746-UM008B-EN-P - December 2006
64 Channel Configuration, Data, and Status
Module default settings for configuration words 0…7 are all zeros.
Scaling defaults are explained on page 78 under the explanation for
the Scaling Select (Bits 13-14).
The channel configuration word consists of bit fields, the settings of
which determine how the channel operates. This procedure looks at
each bit field separately and helps you configure a channel for
operation.
Refer to the Channel Configuration Word (O:e.0 through O:e.3) - Bit
Definitions table on page 66 and the bit field descriptions that follow
for complete configuration information. Page 128 contains a
configuration worksheet that can assist your channel configuration.
Channel Configuration
Procedure The following sections give you procedures to configure the channels.
Configure Each Channel
1. Determine the input device type (RTD type or resistance input)
for a channel and enter its respective four-digit binary code in
bit field 0…3 (Input Type Selection) of the channel
configuration word.
2. Select a data format for the data word value.
Your selection determines how the analog input value from the
A/D converter is expressed in the data word.
3. Enter your two-digit binary code in bit field 4…5 (Data Format
Selection) of the channel configuration word.
Depending upon how you configure these bit settings, you may
have to select a user-set scaling range.
User-set Scaling Using Proportional Counts Data Format on
page 80 gives an example on how to do this.
4. Determine the desired state for the channel data word if a
broken input condition is detected for that channel (open circuit
or short circuit).
5. Enter the two-digit binary code in bit field 6 and 7 (Broken Input
Selection) of the channel configuration word.