SIKA UM RTD.2, Руководство по эксплуатации

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Technical specifications UM RTD.2
- 32 - © SIKA
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Ba_UMRTD.2_en
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01/2019
6 Technical specifications
In the context of metrological quality monitoring, the user may have to carry out a periodic perfor-
mance verification.
The verification must take the standard metrological precautions into consideration. The following in-
structions are to be applied.
The operations are carried out under reference conditions, namely:
•
Room temperature: 23°C
±
5°C.
•
Relative humidity: 45% to 75%.
The standards that constitute the measuring chain must be such that the errors at the check points
are known and are less than or equal to
±
0.008%.
It this verification reveals one or more characteristics of the instrument to be outside the tolerances
specified in the technical specifications chapter, you can:
•
Or return the instrument to the address indicated below for verification and calibration. specifi-
cations
The precision expressions mentioned herein apply from + 18°C to + 28°C, unless otherwise specified,
and are expressed in ± (n % L + C) where L = Reading and C = Constant expressed in practical units,
for a confidence interval of 95%.
They apply to a device positioned in the reference conditions defined after fifteen minutes of pre-
heating.
The precision includes the precision of the reference calibrations, the non-linearity, hysteresis, repeti-
tiveness and long-term stability over the time period mentioned.
6.1 Measurement Function
Rated maximum voltage in common mode: 60 VDC or VAC.
6.1.1 Resistance measurement
The resistance measurement function is obtained by configuring the device as follows:
Sensor: PT100 and Unit: Ohm for the 400 Ω gauge.
Sensor: PT1000 and Unit: Ohm for the 3600 Ω gauge.
Range Scope of measurement Resolution Precision
400 Ω 0 Ω up to 400 Ω 10 mΩ 0.012 % of rdg. + 10 mΩ
3600 Ω 0 Ω up to 3600 Ω 100 mΩ 0.012 % of rdg. +100 mΩ
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Temperature coefficient < 10 ppm/°C from 0°C to 18°C and from 28°C to 50 °C.
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Automatic wiring diagram detection: 2 wires, 3 wires or 4 wires.
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In the 2-wire assembly, the measurement includes the line resistances.
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In the 3-wire assembly, add the line resistances imbalance.
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Measurement current 0.65 mA
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The relative accuracies shown are stated for 360 days and operative conditions from +18°C to
+28°C (+64 °F to +84°F).
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Typical 90 days relative accuracy can be estimated by dividing the “% of rdg” specifications by
1.8.
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Typical 2 year relative accuracy can be estimated by multiplying the “% of rdg” specifications
by 1.5.