Rockwell Automation 1746-NR8 SLC 500 RTD/Resistance Input Module User Manual - Manual (Page 94)

Publication 1746-UM003A-EN-P
7-2 Application Examples
Table 7.1 Channel Configuration Worksheet
(With Settings Established for Channel 0)
Program Listing
Since a 7-segment LED display is used to display temperature, the temperature
data must be converted to BCD. The 16-bit data word representing the
temperature value is converted into BCD values by the program shown in the
following illustration.
Bit Definitions:
Bits 0 through 3
Input Type Select 0000 = 100
Ω
Pt. (385)
0001 = 200
Ω
Pt. (385)
0010 = 500
Ω
Pt. (385)
0011 = 1000
Ω
Pt. (385)
0100 = 100
Ω
Pt. (3916)
0101 = 200
Ω
Pt. (3916)
0110 = 500
Ω
Pt. (3916)
0111 = 1000
Ω
Pt. (3916)
1000 = 10
Ω
Cu (426) (1)
1001 = 120
Ω
Ni (618)
(2)
1010 = 120
Ω
Ni (672)
1011 = 604
Ω
Ni-Fe (518)
1100 = 150
Ω
Potentiometer
1101= 500
Ω
Potentiometer
1110= 1000
Ω
Potentiometer
1111= 3000
Ω
Potentiometer
Bits 4 and 5 Data Format Select
00 = engineering units, x1
(3)
01 = engineering units, x10
(4)
10 = scaled-for-PID (0 to 16383)
11 = proportional counts (-32768 to
+32767)
Bits 6 and 7 Broken Input Select 00 = zero 01 = upscale 10 = downscale 11 = lnvalid
Bit 8 Temperature Units
Select 0 = degrees Celsius 1 = degrees Fahrenheit
Bits 9 and 10 Filter Frequency Select 00 = 28 Hz 01 = 50/60 Hz 10 = 800 Hz 11 = 6400 Hz
Bit 11 Channel Enable 0 = channel disabled 1 = channel enabled
Bit 12 Excitation Current Select 0 = 1.0 mA 1 = 0.25 mA
Bit 13 Cal. Disable 0 = enable 1 = disable
Bits 14 and 15 Lead R. Disable 00 = disable 01 = periodic 10 = always
(1) Actual value at °C is 9.042 Ω per SAMA standard RC21-4-1966.
(2) Actual value at 0°C is 100
Ω
per DIN standard.
(3) Values are in 0.1° /step or 0.1 Ω /step for all resistance input types, except 150 Ω . For the 150 Ω resistance input type, the values are in 0.01 Ω /step.
(4) Values are in 1° /step or 1
Ω
/step for all resistance input types, except 150
Ω
. For the 150
Ω
resistance input type, the values are in 0.1
Ω
/step.