Siemens SITRANS T4200, Руководство по эксплуатации

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Technical data
11.1 Technical data
SITRANS TH200/TH300
Operating Instructions, 06/2010, A5E00393069-03
75
Measuring accuracy
The digital accuracy is the accuracy following analog-to-digital conversion including
linearization and measured value calculation.
The 4 to 20 mA output current is subject to an additional error arising from the digital-to-
analog conversion. This error is called a digital-to-analog error.
The overall error on the analog output under reference conditions is the total of the digital
error and the digital-to-analog error. Where applicable, plus the cold junction error in the
case of thermocouple measurements.
Measuring accuracy
Reference conditions
 Auxiliary power supply
24 V ±1 %

Load
500 Ω

Ambient temperature
23 °C

Interfering fields
None
 Heat-up time
> 5 min
Digital measuring error See table in chapter Digital measuring error (Page 78)
Analog output error (digital-to-analog
error)
< 0.025 % of the output current span (16 mA)
Fault due to internal cold junction < 0.5 °C (0.9 °F)
Ambient temperature influence

Analog measuring error
0.02 % of the output current span (16 mA)/ 10 °C (18 °F)
 Digital measuring error
In resistance thermometers 0.06 °C (0.108 °F)/10 °C (18 °F)
In thermocouples 0.6 °C (1.08 °F)/10 °C (18 °F)
Influence of the auxiliary power supply < 0.001 % of the output current span (16 mA)/V
Influence of load < 0.002 % of the output current span (16 mA)/ 100 Ω
Long-term drift (start of scale value,
measuring span)

< 0.02 % of the measuring span in the first month

< 0.2 % of the measuring span after one year

< 0.3 % of the measuring span after five years