Physical measuring tool It refers to a measuring tool that reproduces or provides one or more known values of a given quantity in a fixed form when used. Such as measuring blocks, square rulers, various curve templates and standard gauges, etc. Limit gauge refers to a special inspection tool without scale. With this tool, the specific size of the inspected workpiece cannot be obtained, but it can determine whether the inspected workpiece is qualified, such as smooth limit gauge, thread limit gauge, etc. Display measuring instrument It refers to the measuring instrument that displays the value. The display can be analog (continuous or non-continuous) or digital, multiple values can be displayed simultaneously, and records can also be provided. Such as analog voltmeter, digital frequency meter, micrometer, etc. Measuring system It refers to a complete set of measuring instruments and other equipment assembled to perform specific measurements. The measuring system can include physical measuring tools. A permanently installed measuring system is called a measuring device. Measurement is actually a process of comparison, that is, a comparison between the measured physical quantity and the standard quantity. Measuring system It refers to a complete set of measuring instruments and other equipment assembled to perform specific measurements. The measuring system can include physical measuring tools. A permanently installed measuring system is called a measuring device.