Campbell CR6 Series, Руководство оператора

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Section 6. Specifications
106
6.1.1.3 Thermistor Measurements — Specifications
The CR6 can measure two-wire thermistors directly using an on- board 5 kΩ
resistor to complete the bridge. A U terminal pair both excites and measures the
thermistor.
Input Resistance: 5 kΩ ±0.1%, 10 ppm/°C
bridge-completion resistor
Measurement
Type: Single-ended voltage
Range: ±5000 mV
Accuracy: ±0.25% of reading
Resolution: 0.001 (Ω RMS)
Speed (vibrating wire and
thermistor combined): < 1 s
6.1.1.4 Resistance Measurements — Specifications
The CR6 makes ratiometric-resistance measurements with voltage and current
excitation.
Resistive Bridges with Voltage
Excitation:
•
Four-wire full bridge
• Six-wire full bridge
• Two-wire half bridge
• Three-wire half bridge
•
Four-wire half bridge
Resistive Bridges with Current
Excitation:
•
Four-wire full bridge
•
Four-wire resistor
Excitation Polarity
Reversal: Minimizes dc error
Accuracy
2,3,4
0 to 40 °C:
±(0.02% of voltage measu offset
5
)
–40 to 70 °C:
±(0.025% of voltage meas offset
5
)
–55 to 85 °C:
±(0.03% of voltage meas offset
5
)
1
Typically, at least one terminal is configured for excitation output. Multiple
sensors can usually use a common excitation terminal.