When you have a question about process automation that needs a short answer, let us know with #WishIknew and @Visaya! We’ll reply with a #WishIknew post. It’ll give a quick explanation, then some related articles, videos, or reviews if you want to know more.
I wish I knew what pressure transmitter calibration is!
Every field device should be calibrated. When you buy a new device, the vendor performs a pressure transmitter calibration and provides you a certificate to confirm that it’s accurate. Of course, entropy happens, so you need to check your device once in a while to make sure it still works correctly.
Companies that demand high accuracy in a pressure transmitter calibration every six months or less. But in general, best practices suggest doing it annually. Today, we have various services that calibrate locally using rings or other tools.
Calibration requires comparing a standard device with high accuracy and a known error to the device under test. You need to go up and down the measuring range to find the error, then adjust the device if its error goes too far out of acceptable margins.
To adjust a pressure transmitter, you need to do the offset trim and the slope trim. I wrote a Q&A post on the concept of offset and slope that you can read here.