Questions regarding the instrument specification sheet
Thread Content
As shown in the diagram, I have two small questions: 1. Isn’t the precision here what we usually refer to as the precision grade? How should we choose the precision when selecting instruments? 2. How should the dimensions of the electrical interface be determined? Can we use options such as M20*1.5, 1/2NPT, or G1/2? Just choosing one of them will suffice
The accuracy of the single-flange Rosemount transmitter is 0.075; accuracy refers to sensitivity, that is, the degree of closeness between the measurement result and the true value. The electrical connector can be chosen arbitrarily; 1/2NPT is the best option.
Different types of instruments have different levels of precision; you just need to remember a few more of them. For electrical connectors, it depends on the number of cores in the instrument cable; NPT and M threads are commonly used. Do not select G thread.
Could you give some examples of the accuracy levels? For things like liquid level, flow rate, and pressure, what are the accuracy values?
For example, the accuracy of a level gauge is ±10 mm. The accuracy of an ultrasonic flow meter is ±0.5% FS, while that of a pressure transmitter is ±0.1% FS. Thermal resistors have class A accuracy. Look at more samples. If you can solve these problems on your own, don’t go to the forum: lol
\ud83d\udc4c\ud83c\udffb
The data sheet is clearly written; a high precision of 0.075 has been selected. For the electrical interface, the standard is M20*1.5, which usually features internal threads; however, 1/2NPT and G1/2 internal threads are also used, depending on the specific application requirements
1. Requirements are specified in the instrument specifications and instrument design manuals. 2. During the early design stage, various disciplines will establish unified regulations for related items in accordance with the instrument specifications, and these regulations will specify the electrical interfaces and accuracy requirements. Therefore, both the preliminary design and the detailed design are carried out in accordance with unified regulations.
In China, the electrical connector standard is mostly M20X1.5, while abroad it is mostly 1/2. The accuracy of Romon is generally 0.075%, while that of domestic products is relatively lower; however, some manufacturers claim to be able to achieve this level of accuracy. Both of the above interfaces come with matching connection hoses or fittings.
Any type of electrical connector will work; the key is that it needs to be used in conjunction with a gland. Glands are usually of M20 or 1/2 NPT type, while G1/2 glands are rare and require customization