Rockwell Automation 1746-NR4 SLC RTD/Resistance Input Module User Manual - Manual (Page 14)

Publication 1746-UM008B-EN-P - December 2006
14 Overview
This table shows the accuracy and temperature drift.
IMPORTANT
The exact signal range valid for each input type is dependent
upon the excitation current magnitude that you select when
configuring the module.
For details on excitation current, refer to page 119.
Accuracy and Temperature Drift Specifications
RTD Unit Type Accuracy
(0.5 mA excitation)
(1)
Accuracy
(0.2 mA excitation)
(1)
Temperature Drift
(0.5 mA excitation)
(2)
Temperature Drift
(0.2 mA excitation)
(2)
Platinum (385)
(3)
100 Ω ±0.1 °C
(±2.0 °F)
±0.5 °C
(±0.9 °F)
±0.034 °C/°C
(±0.061 °F/°F)
±0.014 °C/°C
(±0.025 °F/°F)
200
Ω
±0.1 °C
(±2.0 °F)
±0.5 °C
(±0.9 °F)
±0.034 °C/°C
(±0.061 °F/°F)
±0.014 °C/°C
(±0.025 °F/°F)
500 Ω ±0.6 °C
(±1.1 °F)
±0.5 °C
(±0.9 °F)
±0.017 °C/°C
(±0.031 °F/°F)
±0.014 °C/°C
(±0.025 °F/°F)
1000
Ω
±0.6 °C
(±1.1 °F)
±0.5 °C
(±0.9 °F)
±0.017 °C/°C
(±0.031 °F/°F)
±0.014 °C/°C
(±0.025 °F/°F)
Platinum (3916)
(3)
100 Ω ±1.0 °C
(±2.0 °F)
±0.4 °C
(±0.7 °F)
±0.034 °C/°C
(±0.061 °F/°F)
±0.011 °C/°C
(±0.020 °F/°F)
200
Ω
±1.0 °C
(±2.0 °F)
±0.4 °C
(±0.7 °F)
±0.034 °C/°C
(±0.061 °F/°F)
±0.011 °C/°C
(±0.020 °F/°F)
500 Ω ±0.5 °C
(±0.9 °F)
±0.4 °C
(±0.7 °F)
±0.014 °C/°C
(±0.025 °F/°F)
±0.014 °C/°C
(±0.025 °F/°F)
1000
Ω
±0.5 °C
(±0.9 °F)
±0.4 °C
(±0.7 °F)
±0.014 °C/°C
(±0.025 °F/°F)
±0.014 °C/°C
(±0.025 °F/°F)
Copper (426)
(3)(4) 10
Ω
Not allowed.
(5) ±0.6 °C
(±1.1 °F)
Not allowed.
(5) ±0.017 °C/°C
(±0.031 °F/°F)
Nickel (618)
(3)(6) 120
Ω
±0.2 °C
(±0.4 °F)
±0.2 °C
(±0.4 °F)
±0.008 °C/°
(±0.014 °F/°F)
±0.008 °C/°C
(±0.014 °F/°F)
Nickel (672)
(3) 120
Ω
±0.2 °C
(±0.4 °F)
±0.2 °C
(±0.4 °F)
±0.008 °C/°
(±0.014 °F/°F)
±0.008 °C/°C
(±0.014 °F/°F)
Nickel Iron (518)
(3) 604 Ω ±0.3 °C
(±0.5 °F)
±0.3 °C
(±0.5 °F)
±0.010 °C/°
(±0.018 °F/°F)
±0.010 °C/°C
(±0.018 °F/°F)
(1) The accuracy values assume that the module was calibrated within the specified temperature range of 0…60 °C (32…140 °F).
(2)
Temperature drift specifications apply to a module that has not been calibrated.
(3) The digits following the RTD unit type represent the temperature coefficient of resistance ( ∝), which is defined as the resistance change per ohm per °C. For instance,
Platinum 385 refers to a platinum RTD with ∝ = 0.00385 Ω/Ω -°C or simply 0.00385 /°C.
(4)
Actual value at 0 °C (32 °F) is 9.042 Ω per SAMA standard RC21-4-1966.
(5) To maximize the relatively small RTD unit signal, only 2 mA excitation current is allowed.
(6) Actual value at 0 °C (32 °F) is 100 Ω per DIN standard.