NI1000 specification
Electrical measuring range used | 2000 Ω | 5000 Ω | ||
|---|---|---|---|---|
Connection | 4-wire | 2/3-wire 1) | 4-wire | 2/3-wire 1) |
Starting value | -60°C | -200°C | ||
End value | 151°C | 850°C | ||
Basic accuracy: Measuring deviation at 23°C terminal environment, with averaging, typ. | < ±(tbd) K | < ±(tbd) K | < ±(tbd) K | < ±(tbd) K |
Temperature coefficient 2), typ. | < tbd mK/K | < tbd mK/K | < tbd mK/K | < tbd mK/K |
PDO LSB (Legacy Range only) | 0.1/0.01/0.001°C/digit, depending on PDO setting | |||
1) See initial remarks about 2/3-wire operation. The offset specification does not apply in 2-wire operation, as the offset is increased due to the connection. In 2-wire operation, an offset compensation is to be carried out after installation; refer to the ELM's internal functions Tare (chapter “ELM Features“/ “Tare“) or Zero Offset (chapter “ELM Features“/ “ZeroOffset“). The given offset specification of the terminal thus plays practically no further part. The offset deviation of a resistance measurement can change over time, therefore Beckhoff recommends a regular offset compensation or attentive monitoring of the change.
2) The temperature coefficient, i.e. the change in the measured temperature value in relation to the change in the ambient temperature of the terminal, is not constant, as can be seen in the following plot. The value at a sensor temperature of 0 °C is given here as an orientation value. Further values can be taken from the plot.