Rockwell Automation 1746-NR4 SLC RTD/Resistance Input Module User Manual - Manual (Page 76)

Publication 1746-UM008B-EN-P - December 2006
76 Channel Configuration, Data, and Status
Temperature Units Selection (Bit 8)
The Bit Descriptions for Temperature Units Selection table shows the
description for bit 8. The temperature units bit lets you select
temperature engineering units in °C or °F for RTD input types. This bit
field is only active for RTD input types. It is ignored when the
resistance input type is selected.
Filter Frequency Selection (Bits 9 and 10)
The Bit Descriptions for Filter Frequency Selection table shows the
descriptions for bits 9 and 10. The channel filter frequency bit field
lets you select one of four filters available for a channel. The filter
frequency affects the channel update time and noise rejection
characteristics (refer to chapter 4 for details).
Channel Enable Selection (Bit 11)
The Bit Descriptions for Channel Enable Selection table shows the
description for bit 11. You use the channel enable bit to enable a
channel. The RTD module only scans those channels that are enabled.
To optimize module operation and minimize throughput times, you
should disable unused channels by setting the channel enable bit to
zero.
Bit Descriptions for Temperature Units Selection
Binary
Value Select If you want to
0 Degrees Celsius Display the channel data word in degrees Celsius
1 Degrees Fahrenheit Display the channel data word in degrees Fahrenheit
Bit Descriptions for Filter Frequency Selection
Binary
Value Select Description
00 10 Hz Provide both 50 Hz and 60 Hz ac line noise filtering. This setting
increases the channel update time, but also increases the noise
rejection.
01 50 Hz Provide 50 Hz ac line noise filtering.
10 60 Hz Provide 60 Hz ac line noise filtering.
11 250 Hz Provide 250 Hz ac noise filtering. This setting decreases the noise
rejection, but also decreases the channel update time.