If the positive and negative chambers of a Rosemount differential pressure transmitter are open to the atmosphere, what should the indicated differential pressure be?
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I have a question for the teachers: The facility uses Rosemount differential pressure transmitters connected to double-chamber balance vessels to measure the level of liquid in the steam drum. The high-pressure side of the condensate in the two-chamber balance vessel is connected to terminal L of the transmitter, while the low-pressure side of the drum water is connected to terminal H of the transmitter. 1. Is a zero-point migration necessary for this type of integration? 1. If the transmitter has undergone negative zero-point shift, then by closing the positive and negative pressure valves, the positive and negative pressure chambers are left empty. What value should the differential pressure displayed on the gauge be? Is the displayed value related to the amount of negative zero-point shift? 2. If the transmitter has not had its zero point adjusted, then with the positive and negative pressure valves closed and the positive and negative pressure chambers at atmospheric pressure, what value should the differential pressure displayed on the gauge be?
1. Who the hell knows how much it shows? . . . . . Who knows who the dog is~~~~~~~, :P 2. It shows how much, and you migrate that much white.
1. Migration must be carried out. 2. The amount of data to be migrated is not determined based on static conditions; factors such as temperature and pressure under operational conditions need to be taken into account, and the amount of data to be migrated must be calculated accordingly. First, you need to determine what structure the double-pressure vessel you are using has; I have seen two types. Regarding the calculation of the amount of data to be migrated, you can find information by searching online.
1. Migration must be carried out. 2. The value displayed represents the amount of migration that has taken place; the differential pressure value remains unchanged during migration, but the percentage range changes and should become 0. 3. It should display -ρ Hg, where ρ is the density of the filling fluid and H is the distance between the flanges on the high and low pressure sides
Have you reversed it? The high-pressure side of the condenser should be connected to H, and the low-pressure side to L. Under normal circumstances, if a migration has been performed and the gauge reads nothing, the pressure value should be around the 4 milliamp setting
Negative migration is certain. . . As for the amount of migration and the values displayed on the on/off meter, I’ve heard that it’s better to conduct experiments on-site. . . First, have the maintenance team fill the drum with liquid, and then check the status of the instruments. . . . Second, after draining half of the liquid level, check the status. . . This gives you an intuitive feeling. . .