Rockwell Automation 1746-NT4 Series B,D17466.6.1 SLC 500 4-Channel Thermocouple/mV Input Module User Manual - Manual (Page 106)

Publication 1746-UM007C-EN-P - July 2004
B-2 NT4 Configuration Worksheet
3. Determine the desired state for the channel data word if an open
circuit condition is detected for that channel. Enter the 2-digit
binary code in bit field 6-7 of the channel configuration word.
4. If the channel is configured for thermocouple inputs or the CJC
sensor, determine if you want the channel data word to read in
degrees Fahrenheit or degrees Celsius and enter a one or a zero
in bit 8 of the configuration word. If the channel is configured
for a mV analog sensor, enter a zero in bit 8.
5. Determine the desired input filter for the channel and enter the
2-digit binary code in bit field 9-10 of the channel configuration
word. A smaller filter frequency increases the channel update
time, but also increases the noise rejection and channel
resolution. A larger filter frequency decreases the noise rejection,
but also decreases the channel update time and channel
resolution.
6. If the channel will be used in your system it must be enabled.
Place a one in bit 11 if the channel is to be enabled. Place a zero
in bit 11 if the channel is to be disabled.
7. Ensure that bits 12-15 contain zeros, and then enter all the bit
setting selected in previous steps to complete the configuration
word.
8. Build the channel configuration word for every channel that is
being used on each thermocouple/mV module repeating the
procedures given in steps 1-7.
Bits 6 and 7 Open Circuit Select 00 = zero 01 = upscale 10 = downscale
Bit 8 Temperature Units Select 0 = degrees Celsius 1 = degrees Fahrenheit
Bits 9 and 10 Filter Frequency Select 00 = 10 Hz 01 = 50 Hz 10 = 60 Hz 11 = 250 Hz
Bit 11 Channel Enable 0 = channel disabled 1 = channel enabled
Bits 12–15 Not Used 0000 = always make this setting