Pyromation Series 642 - Manual (Page 36)

Technical data Series 642
36 Pyromation, Inc.
Influence of supply voltage
≤ ±0.005%/V deviation from 24 V, related to the full scale value
Long-term stability ≤ 0.1 K (0.18 °F)/year or ≤ 0.05%/year
Data under reference conditions. % relates to the set span. The larger value applies.
Influence of ambient
temperature (temperature
drift) Total temperature drift = input temperature drift + output temperature drift
Examples for calculating the accuracy:
• Example 1
Input temperature drift
Δϑ = 10 K (18 °F), Pt100, span 0 to 100 °C (32 to 212 °F)
Maximum process value: 100 °C (212 °F)
Measured resistance value: 138.5
Ω (see IEC 60751)
Typ. influence in
Ω: (0.002% of 138.5 Ω) * 10 = 0.0277 Ω
Conversion Ω to °C: 0.0277 Ω / 0.4 Ω/K = 0.07 K (0.013 °F)
• Example 2
Input temperature drift
Δϑ = 10 K (18 °F), thermocouple type K with span 0 to 600 °C (32 to
1112 °F)
Maximum process value: 600 °C (1112 °F)
Measured thermoelectric voltage: 24905
μV (see IEC584)
Typ. influence in
μV: (0.002% of 24905 μV) * 10 = 5 μV
Conversion Ω to °C: 5 μV / 40 μV/K = 0.12 K (0.216 °F)
• Example 3
Output temperature drift
Δϑ = 10 K (18 °F), measuring range 0 to 100 °C (32 to 212 °F)
Span: 100 K (180 °F)
Typical influence: (0.002% of 100 K) * 10 = 0.02 K; (0.002% of 180 °F) * 10 = 0.036 °F
Δϑ = deviation of ambient temperature from the reference operating condition
Total measuring point error = max. possible measured error + temperature sensor error
Influence of cold junction Pt100 DIN IEC 60751 Cl. B (internal cold junction with thermocouples TC)
Effect on the accuracy when ambient temperature changes by 1 K (1.8 °F)
Input 10 to 400 Ω 0.002% of measured value
Input 10 to 2000 Ω 0.002% of measured value
Input -20 to 100 mV typ. 0.002% of measured value (maximum value = 1.5 x typ.)
Input -5 to 30 mV typ. 0.002% of measured value (maximum value = 1.5 x typ.)
Output 4 to 20 mA typ. 0.002% of measured value (maximum value = 1.5 x typ.)
Typical sensor resistance change when process temperature changes by 1 K (1.8 °F):
Cu10: 0.04 Ω Pt200: 0.8 Ω Ni120: 0.7 Ω Cu50: 0.2 Ω Pt50: 0.2 Ω
Cu100, Pt100: 0.4 Ω Pt500: 2 Ω Pt1000: 4 Ω Ni100: 0.6 Ω Ni1000: 6 Ω
Typical change in thermoelectric voltage when process temperature changes by 1 K (1.8 °F):
B: 10 μV C: 20 μV D: 20 μV E: 75 μV J: 55 μV K: 40 μV
L: 55 μV N: 35 μV R: 12 μV S: 12 μV T: 50 μV U: 60 μV