Datasheet

21
System accuracy specications
The U2802A system accuracy specifications are shown in Table 1, Table 2, and Table 3. These measurements are derived from
the U2802A and DAQ input accuracy specifications without including the thermocouple error. Refer to “Calculating System
Accuracy” section in the Keysight U2802A 31-Channel Thermocouple Input Device User’s Guide for calculation methodology.
Table 1. Measurement accuracy of the U2355A and U2356A at 23 °C ± 5 °C
Thermocouple measurement accuracy (U2355A, U2356A at 23 °C ± 5 °C)
T/C type
ITS-90 Temperature range (°C)
Optimum measurement
range(°C)
Without
averaging
(± °C)
50 points
averaging
(± °C)
500 points
averaging
(± °C)Low High Low High
B 0 1820 1100 1820 1.9 1.2 1.0
400 1100 4.4 2.5 2.0
E –270 1000 –150 1000 1.7 1.6 1.6
–200 –150 2.4 2.3 2.3
J –210 1200 –150 1200 1.6 1.5 1.5
–210 –150 2.7 2.6 2.5
K –270 1372 –100 1200 1.5 1.4 1.4
–200 –100 2.7 2.6 2.6
N –270 1300 –100 1300 1.5 1.3 1.3
–200 –100 3.0 2.7 2.6
R –50 1768 300 1760 2.0 1.4 1.3
–50 300 5.0 3.1 2.6
S –50 1768 400 1760 2.1 1.6 1.4
–50 400 4.5 2.8 2.4
T –270 400 –100 400 1.5 1.4 1.4
–200 –100 2.7 2.5 2.5
Table 2. Measurement accuracy of the U2355A at 0 to 18 °C and 28 to 45 °C
Thermocouple measurement accuracy (U2355A at 0 to 18 °C and 28 to 45 °C)
T/C type
ITS-90 Temperature range (°C)
Optimum measurement range
(°C)
Without
|averaging
(± °C)
50 points
averaging
(± °C)
500 points
averaging
(± °C)Low High Low High
B 0 1820 1100 1820 3.4 2.4 2.2
400 1100 7.5 3.6 2.2
E –270 1000 –150 1000 2.7 2.6 2.5
–200 –150 3.8 3.6 3.6
J –210 1200 –150 1200 2.5 2.4 2.4
–210 –150 4.2 4.0 3.9
K –270 1372 –100 1200 2.9 2.8 2.8
–200 –100 4.3 4.0 3.9
N –270 1300 –100 1300 2.6 2.5 2.5
–200 –100 4.9 4.2 4.0
R –50 1768 300 1760 3.8 3.1 3.0
–50 300 8.5 4.6 3.3
S –50 1768 400 1760 4.2 3.4 3.2
–50 400 7.7 4.2 3.1
T –270 400 –100 400 2.4 2.2 2.2
–200 –100 4.3 4.3 3.9