Feels like a chicken and egg senario. Let’s say I get my torque wrench from work sent off to be calibrated, and that’s calibrated with something itself needs to be calibrated, and so on and so fourth. How’s that figured out?
In: 430
Same problem here….how programing language (c++, java etc) are programmed in first place?
in my college electronics classes measurement tools were calibrated with other precision tools. its called metrology. you have to use a tool thats a certain amout more accurate than the one youre calibrating and so on and so forth. in college we had little handheld old school analog meters. we also had the machine to calibrate them that took up an entire table and was heavy as hell.
at the lab i work at we have a guy from the manufacture(s) come in a calibrate our tools. every 6mo or year depending on tool.
With something like a torque wrench, you can calibrate it with an ordinary scale/balance. Multiply the force applied to the wrench by the length of the lever arm to get the torque, then compare that to the setting on the wrench. Don’t forget to account for the torque from weight of the wrench itself.
It used to be that we had physical objects that were by definition calibrated. Whenever we wanted to calibrate an instrument to the highest degree so we could use it to calibrate other instruments we would use this object to calibrate the instrument and by definition the object would be calibrated.
The issue with this was that these objects changed slightly over time. So the definition changed. For example when the master kilogram lost a tiny bit of weight over some time then the definition of the kilogram changed and all the calibrated instruments were now out of calibration.
In order to fix this we are now using the resault of carefully chosen experiments. So you can measure a physical property, such as the speed of light, and you will by definition know the resault, if you get a different resault it is because your instrument is out of calibration so you need to have it adjusted.
The key to calibration is traceability. If I buy a calibrated tool, the company that calibrated it used their local standard. In the paper work they provide me, they include provenance showing when their local standard was last calibrated, and what it was calibrated to. In the US, these chains of provenance typically lead to a standard approved by the National Institute of Standards and Technology, a part of the US government.
A way of manufacturing a precision device is created then other devices using a similar mechanism can be calibrated. A device is made that derives it’s calibration from some universal element. Another device is then calibrated against this. If the original device is inaccurate then sometimes the error can he calculated very accurately or the average of a number of readings from a number of devices are taken.
Feels like a chicken and egg senario. Let’s say I get my torque wrench from work sent off to be calibrated, and that’s calibrated with something itself needs to be calibrated, and so on and so fourth. How’s that figured out?
In: 430
Same problem here….how programing language (c++, java etc) are programmed in first place?
in my college electronics classes measurement tools were calibrated with other precision tools. its called metrology. you have to use a tool thats a certain amout more accurate than the one youre calibrating and so on and so forth. in college we had little handheld old school analog meters. we also had the machine to calibrate them that took up an entire table and was heavy as hell.
at the lab i work at we have a guy from the manufacture(s) come in a calibrate our tools. every 6mo or year depending on tool.
With something like a torque wrench, you can calibrate it with an ordinary scale/balance. Multiply the force applied to the wrench by the length of the lever arm to get the torque, then compare that to the setting on the wrench. Don’t forget to account for the torque from weight of the wrench itself.
It used to be that we had physical objects that were by definition calibrated. Whenever we wanted to calibrate an instrument to the highest degree so we could use it to calibrate other instruments we would use this object to calibrate the instrument and by definition the object would be calibrated.
The issue with this was that these objects changed slightly over time. So the definition changed. For example when the master kilogram lost a tiny bit of weight over some time then the definition of the kilogram changed and all the calibrated instruments were now out of calibration.
In order to fix this we are now using the resault of carefully chosen experiments. So you can measure a physical property, such as the speed of light, and you will by definition know the resault, if you get a different resault it is because your instrument is out of calibration so you need to have it adjusted.
The key to calibration is traceability. If I buy a calibrated tool, the company that calibrated it used their local standard. In the paper work they provide me, they include provenance showing when their local standard was last calibrated, and what it was calibrated to. In the US, these chains of provenance typically lead to a standard approved by the National Institute of Standards and Technology, a part of the US government.
A way of manufacturing a precision device is created then other devices using a similar mechanism can be calibrated. A device is made that derives it’s calibration from some universal element. Another device is then calibrated against this. If the original device is inaccurate then sometimes the error can he calculated very accurately or the average of a number of readings from a number of devices are taken.
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