What is the migration of differential pressure transmitters?
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What is the migration of differential pressure transmitters? I hope someone knowledgeable can explain this to me. Thank you!
It’s just the transmitter being moved, from location A to location B.
Migration of differential pressure transmitters, migration of liquid levels: When using a differential pressure transmitter to measure liquid levels, if the positive and negative pressure chambers of the transmitter are at the same level as the pressure sampling points in the container, no migration is required. In practical applications, due to considerations such as the installation location of the equipment and ease of maintenance, it is not always necessary for the measuring instruments to be at the same level as the pressure sampling points ； For example, when the medium to be measured is a highly corrosive or highly viscous liquid, it is not possible to introduce this medium directly into the pressure measuring instrument; therefore, an isolation fluid tank must be installed, using the isolation fluid to transmit pressure signals and thus prevent the measuring instrument from being corroded. At this point, it is necessary to consider the effect of the liquid columns of the medium and the isolation fluid on the readings of the pressure measuring instrument. There are mainly three installation methods for differential pressure transmitters used to measure liquid levels. In order to accurately indicate the level of the liquid, the differential pressure transmitter must undergo certain technical adjustments – namely calibration. Migration is divided into no migration, negative migration, and positive migration.
Simply put, when the liquid level is at zero, the transmitter’s output is not zero; therefore, it is necessary to adjust the transmitter’s zero point while keeping the range unchanged. This is what is known as zero point shift. When the liquid level is at zero, and the pressure on the positive side of the transmitter is greater than the pressure on the negative side, positive migration is required ； When the liquid level is at zero, negative migration is required if the pressure on the negative side of the transmitter is greater than the pressure on the positive side.
The migration of a differential pressure transmitter refers to zero-point migration, with the range remaining unchanged
Keep in mind that the purpose of migration is to correct the zero point
Migration is the process of moving a zero point from one place to another...
It’s about correcting the pressure values corresponding to 4.20 milliamps
Thank you, it was explained in simple terms.