DH Instruments E-DWT-H, Руководство по эксплуатации и обслуживанию

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E-DWT-H OPERATION AND MAINTENANCE MANUAL
© 2009 DH Instruments, a Fluke Company Page 4
Warm Up Time 15 minute temperature stabilization recommended from
cold power up.
Normal Operating Temperature Range 10 to 40 °C
Resolution Default: 0.01 % of active range.
User adjustable to 1 ppm of Q-RPT maximum or 10 ppm
of active AutoRange, whichever is larger.
Precision
1
± 0.018% of reading or 0.0018% of Q-RPT span,
whichever is greater
Predicted Stability
2
One year: ± 0.0075% of reading or 0.0008% of Q-RPT
span, whichever is greater
Two year: +/- 0.015% of reading or 0.0015% of Q-RPT
span, whichever is greater
Measurement Uncertainty
3
One year: ± 0.02% of reading or 0.002% of Q-RPT span,
whichever is greater
Two year: ± 0.025% of reading or 0.0025% of Q-RPT
span, whichever is greater
1. Combined linearity, hysteresis, and repeatability.
2. Predicted Q-RPT measurement stability limit (k=2) assuming regular use of AutoZero function and
short term stability between rezeroing. As stability can only be predicted and varies from Q-RPT to
Q-RPT, stability for a specific Q-RPT should be established from experience.
3. Maximum deviation of the Q-RPT indication from the true value of applied pressure including
precision, predicted stability with rezeroing, temperature effect from 10 to 40 ºC and calibration
uncertainty (assumes calibration reference uncertainty of ±0.005% of reading, k=2), combined and
expanded (k=2) following the ISO “Guide to the Expression of Uncertainty in Measurement.”
1.2.3.2 On-Board Barometer
The measurement uncertainty of the on-board barometer is not significant to
E-DWT-H measurement uncertainty. The barometer is used only to measure
small, short term changes in atmospheric pressure to provide dynamic
compensation of the Q-RPT’s atmospheric pressure offset in gauge pressure
measurement mode (see Section 3.9.1)
Sensor Technology: Micro-machined silicon
Warm Up Time: None required
Resolution: 0.1 Pa (0.000015 psi)