Let’s look for mistakes together
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Which of these two calibration sheets for pressure transmitters is more standardized, and what are the specific basic errors present in each? Everyone shares their opinions
Does the term “remote transmission level transmitter” mentioned in the diagram refer to a capillary-oiled remote transmission double-flange differential pressure level transmitter? If that’s the case, then the data on this verification form is seriously inaccurate; it must have been fabricated. Why? Because whenever capillaries are used for long-distance transmission, the hysteresis performance of the instrument cannot be very good – it cannot reach 0.002 mA. 0.002 ÷ (20 – 4) = 0.0125% FS, which is less than two ten-thousandths. As for a 10 kPa range, even if one tried hard, it would still be impossible to achieve a hysteresis performance of 0.0125% FS for double-flange designs.
Is the current value recorded as 0.01mA? Is it possible to use a multimeter with poor accuracy of three and a half or four and a half digits to test a voltage transformer with millivolt-level accuracy? Hehe, at least it’s a test of ability, but it’s seriously inadequate. Judging from the data formatting, this verification form wasn’t prepared by someone with experience in measurement and verification; I guess it was just made up by someone random. :lol
The first specification is fine, but the second one has many issues: there is no information on the standard instruments used for calibration, no units specified, no tolerance values given; the ‘k’ in kPa is in lowercase, and the number of decimal places recorded is not consistent...
Furthermore, these meters are of a quality level 0.1 above the national standards; they are claimed to have an accuracy of ten-thousandth grade. With such high precision, when these meters are sent to the metrology institute for calibration, they are usually calibrated at 11 points, and the number of calibration points must be no less than 9. The two inspection sheets provided by the poster are based on 5-point inspection, and the number of inspection points is insufficient; thus, there is not enough basis to determine that the instrument meets the standards. . . Make up some data, and do it in such a fake way... Hehehe.... What an idiot. :lol :lol