I suddenly realized that the range of 0–2 MPa is an incorrect representation! ,.. Welcome to discuss. . .
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This post was last edited by 1111111 on 2016-4-28 01:01. I suddenly realized that the range of 0–2 MPa is an incorrect representation! In other words, it has serious defects; discussions are welcome. . . Why is it said to have errors and defects? Here are some examples: 1. For instance, if a gauge has a resolution of 0.001 MPa, then its reading of 0 MPa actually corresponds to a value of 0.000 MPa. The true value corresponding to this 0.000 MPa could be any value within the range of ±0.0004 MPa, and it’s impossible to determine exactly which value it is. 2. On the other hand, if another gauge has a resolution of 0.0001 MPa, then its reading of 0 MPa corresponds to a value of 0.0000 MPa; in this case, we can accurately determine every pressure value within the range of ±0.0004 MPa. 3. By comparing these two examples, it’s clear that since the resolutions of the gauges differ, the meaning of the reading of 0 MPa also varies, and thus the level of precision differs as well! In other words, 0.000 MPa and 0.0000 MPa are not equivalent in terms of measurement; it cannot be said that both are 0 MPa, understand? 4. For another example, when both of the aforementioned tables have a precision of 0.2 level, can you tell the difference in their measurement capabilities from a range of 0～2MPa? 5. Do you understand? 0 MPa, 0.0 MPa, 0.00 MPa, 0.000 MPa, 0.0000 MPa, 0.00000 MPa, … These values have different statistical meanings; it is incorrect to say that they are all equal to 0 – this is a serious mistake. These values have different statistical meanings; it is incorrect to say that they are all equal to 0 – this is a serious mistake. These values have different statistical meanings; it is incorrect to say that they are all equal to 0 – this is a serious mistake. 6. In my opinion, it is necessary to reform the way “range 0–2 MPa” is expressed, in order to better describe the measurement capabilities of the instrument. . . I suggest changing it to this: 0.001–2MPa, 0.0001–2MPa, 0.00003–2MPa, 0.000005–2MPa. The lower limit of the measurement range should be set as the resolution of the gauge; after all, that represents the minimum resolution with which the gauge can make measurements. It’s not some arbitrary value like 0MPa, right? 7. Discussions are welcome. Discussions are welcome. Discussions are welcome. 8. Many people don’t really understand the relationship between a gauge’s measurement resolution and its ability to resist electromagnetic interference. I’ll discuss this in a separate post
The range is the difference between the upper and lower measurement limits; 0–2 MPa is the measurement range, not the range.
This post was last edited by 1111111 on 2016-4-28 07:48. Thank you for following! The “Range: 0~2MPa” indicated on the instrument’s label refers to the measurement range. As for the difference between the upper and lower limits of measurement, it is commonly referred to as the range span, range width, full scale, or FS. For example, in the case of -500Pa~500Pa, we would say that the span is 1000Pa, and FS = 1000Pa
There’s no need to worry too much; just write a paper on this and publish it – you might even win a Nobel Prize. You’ll be able to change a certain habit
The poster can take a good look at the dead zone and accuracy.
Details reveal the truth; whether something is changed or not, it represents progress in any case. Progress in awareness and mindset is very important. Another important point is that I don’t quite understand the causal relationship between a meter’s measurement resolution and its ability to resist electromagnetic interference. I’m an outsider who doesn’t know much about this, so I’m here to learn.
It should be written as 0.000-2.000, right?
Thank you for participating! The reason I recommend writing it as 0.001–2 MPa rather than 0.000–2 MPa is based on the following considerations: 1. It is necessary to clearly inform the user of the instrument about its resolution, especially for pressure gauges with high resolution and strong interference resistance, such as those with 5-digit, 6-digit, or 7-digit displays; in some cases, the resolution at the least significant digit is not 1 unit but 2, 3, 4, or 5 units. 2. I also considered using the format of ±0.001–2 MPa, but after careful thought, I felt that writing it as 0.001–2 MPa is more concise and precise. 3. When the zero point of an instrument is very stable—for example, if a 4-digit display pressure gauge has a stable zero point—then when observing its zero value over minutes or hours, you will find that it naturally fluctuates between -0.001, 0.000, and 0.001. Please note: A stable zero point is characterized by natural fluctuations within the range of the minimum resolution; it will never remain fixed at 0.000 like a “zombie” value! Please note: A typical characteristic of zero stability is natural oscillation at the minimum resolution; it will by no means remain fixed at 0.000 like a zombie! Please note: A typical characteristic of zero stability is natural oscillation at the minimum resolution; it will by no means remain fixed at 0.000 like a zombie! So, presenting the value in the format of 0.001–2 MPa prevents any misunderstanding that the starting point of the scale is not 0. Those who have adjusted and calibrated scales know that when the zero point is set to -0.001, 0.000, or 0.001, it’s assumed to be properly adjusted and no further adjustments are made. Few people go to the trouble of setting it to 0.000. And even if someone particular about precision does manage to set it to 0.000, in just a few minutes, perhaps while they’re busy taking notes, the measured value will naturally fluctuate back to -0.001 or 0.001. :lol Wouldn’t their effort and diligence then be in vain? That’s why, it’s only by relying on science that we can achieve efficiency; science is everywhere :lol
Great Chinese posts – yes, that’s the way to do it. What was done in the past wasn’t incorrect; it was just not scientific enough. Science is relative, not wrong. For example, using a vernier caliper to measure the diameter of a shaft of 50 units is more scientific than using a tape measure; yet measuring with a tape measure is also correct, it’s just less scientific. Only through scientific methods can accuracy be ensured, and efficiency can be **improved**.
You make it sound so complicated. . . I don’t understand. . . When selecting a general transmitter, factors such as accuracy, detection limit, range, transduction ratio, and linear error are taken into consideration – isn’t that sufficient?
Resolution is another metric; it is also related to accuracy and is reflected in “precision” as well. Actually, there is no need to write things like 0.00~2Mpa; accuracy or uncertainty can reflect that already.