Appendices
Specifications
A
A-7

Input Impedance

100 M minimum in parallel with 150 pF maximum

Common Mode and Normal Mode Rejection

See the specifications for dc voltage measurements.

Cross-Talk Rejection

Refer to Appendix B.

Open Thermocouple Detect

Small ac signal injection and detection scheme before each measurement detects greater

than 1 to 4 k as open. Performed on each channel unless defeated by computer

command

Temperature Measurements (RTDs)
Accuracy

See Table A-7, A-8 and A-9.

Table A-7. Temperature Measurements - Accuracy (RTDs) (IEC751 Amendment 2) (ITS-90)
RTD 4-Wire Accuracy* (±°C)
Temperature Resolution 18°C to 28°C 0°C to 60°C
(°C) Slow Fast 90 Day
Slow 1 Year
Slow 1 Year
Fast 1 Year
Slow 1 Year
Fast
-200.00 0.02 0.1 0.05 0.05 0.47 0.06 0.48
0.00 0.02 0.1 0.08 0.09 0.55 0.13 0.59
100.00 0.02 0.1 0.10 0.10 0.58 0.17 0.64
300.00 0.02 0.1 0.13 0.14 0.65 0.24 0.75
600.00 0.02 0.1 0.19 0.20 0.76 0.36 0.92
* Sensor inaccuracies are not included
Table A-8. Temperature Measurements - Accuracy (RTDs) (IEC751 Amendment 1) (ITS-90)
RTD 4-Wire Accuracy* (±°C)
Temperature Resolution 18°C to 28°C 0°C to 60°C
(°C) Slow Fast 90 Day
Slow 1 Year
Slow 1 Year
Fast 1 Year
Slow 1
Year
Fast
-200.00 0.02 0.1 0.11 0.11 0.53 0.12 0.54
0.00 0.02 0.1 0.09 0.09 0.55 0.13 0.59
100.00 0.02 0.1 0.11 0.11 0.59 0.18 0.65
300.00 0.02 0.1 0.19 0.20 0.70 0.30 0.81
600.00 0.02 0.1 0.44 0.45 1.01 0.61 1.17
* Sensor inaccuracies are not included