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NI 9219 Calibration Procedure
Test Conditions
The following setup and environmental conditions are required to ensure the NI 9219
meets
published specifications.
•
Keep connections to the device as short as possible. Long cables and wires act as antennas,
picking up extra noise that can affect measurements.
•
Verify that all connections to the device are secure.
•
Use shielded copper wire for all cable connections to the device. Use twisted-pairs wire to
eliminate noise and thermal offsets.
•
Maintain an ambient temperature of 23 ± 5 °C. The device temperature will be greater than
the ambient temperature.
•
Keep relative humidity below 80%.
•
Allow a warm-up time of at least 10 minutes to ensure that the NI 9219 measurement
circuitry is at a stable operating temperature.
Discrete
Resistors
—
RTD Accuracy
TCR:
≤
10 ppm/°C
Resistor values: 4020
Ω
± 1%, 402
Ω
± 1%, 20
Ω
± 5%, 4.99
Ω
± 5%
Resistance
Accuracy
TCR:
≤
10 ppm/°C
Resistor values: 8450
Ω
± 1%, 845
Ω
± 1%, 20
Ω
± 5%
Quarter-Bridge
Accuracy
TCR:
≤
10 ppm/°C
Resistor values: 309
Ω
± 1%, 121
Ω
±
1%, 4.99
Ω
± 5%
Half-Bridge
Accuracy
TCR:
≤
10 ppm/°C
Resistor values: 1 k
Ω
± 1% (x2)
Full-Bridge
Accuracy
TCR:
≤
10 ppm/°C
Resistor values: 10 k
Ω
± 1% (x2)
cDAQ
Chassis
NI cDAQ-9178
All
—
Connection
Accessory
NI 9972
All
—
Table 1.
Recommended Equipment (Continued)
Equipment
Recommended
Model
Where Used
Minimum Requirements