Rockwell Automation 1746-NR8 SLC 500 RTD/Resistance Input Module User Manual - Manual (Page 65)

Publication 1746-UM003A-EN-P
Channel Configuration, Data, and Status 4-17
Temperature Units Selection (Bit 8)
The following 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.
Table 4.21 Bit Descriptions for Temperature Units Selection
Filter Frequency Selection (Bits 9 and 10)
The following 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 3 for details).
Table 4.22 Bit Descriptions for Filter Frequency Selection
Channel Enable Selection (Bit 11)
The next 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.
When set (1), the channel enable bit is used by the module to read the
configuration word information you have selected. While the enable bit is set,
modification of the configuration word may lengthen the module update time
for one cycle. If any change is made to the configuration word, the change
must be reflected in the status word before new data is valid. (Refer to Channel
Status Checking on page 4-19.)
Binary
Value Select If you want to
0 °C display the channel data word in °C.
1 °F display the channel data word in °F.
Binary
Value Select Description
00 28 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 50/60 Hz Provide both 50 Hz and 60 Hz AC line noise filtering.
10 800 Hz Provide 800 Hz AC line noise filtering.
11 6400 Hz Provide 6400 Hz AC noise filtering. This setting decreases the
noise rejection, but also decreases the channel update time.