Rockwell Automation 1746-NR4 SLC RTD/Resistance Input Module User Manual - Manual (Page 16)

Publication 1746-UM008B-EN-P - December 2006
16 Overview
Resistance Device Compatibility
The following table lists the resistance input types you can use with
the RTD module and gives each type’s associated specifications.
Hardware Overview
The RTD module fits into a single-slot of an SLC 500 chassis.
• Modular system, except the processor slot (0)
• Fixed system expansion chassis (1746-A2)
The module uses eight input words and eight output words.
The module contains a removable terminal block (item 3) providing
connection for any mix of four RTD sensors or resistance input
devices. There are no output channels on the module. Module
configuration is done via the user program. There are no DIP
switches.
Resistance Input Specifications
Input Type Resistance Range
(0.5 mA excitation) Resistance Range
(2.0 mA excitation)
Accuracy
(1) Temperature
Drift Resolution Repeatability
Resistance
150 Δ 0…150 Δ 0…150 Δ (2) (3) 0.01 Δ x 0.04 Δ
500
Δ
0…500
Δ
0…500
Δ
x 0.5
Δ
x 0.014
Δ/ ° C
(x 0.025 Δ/ ° F
0.01
Δ
x 0.2
Δ
1000
Δ 0…1000 Δ
0…1000
Δ
x 1.0
Δ
x 0.029
Δ/ ° C
(x 0.052
Δ/ ° F
0.01
Δ
x 0.2
Δ
3000 Δ 0…3000 Δ 0…1900 Δ x 1.5 Δ x 0.043 Δ/ ° C
(x 0.077 Δ/ ° F
0.01 Δ x 0.2 Δ
(1)
The accuracy values assume that the module was calibrated within the specified temperature range of 0…60 °C (32 …140 °F).
(2) The accuracy for 150 Ω is dependant on the excitation current:
x 0.2 Ω at 0.5 mA
x 0.15 Ω at 2.0 mA
(3) The temperature drift for 150 Ω is dependant on the excitation current:
x 0.006 Ω/°C at 0.5 mA
x 0.004 Ω at 2.0 mA
IMPORTANT
If the RTD module resides in a remote configuration with a
SLC 500 Remote I/O Adapter Module (1747-ASB), use block
transfer for configuration and data retrieval. Block transfer
requires a 1747-SN Remote I/O Scanner (series B) or PLC
processor.