Question on Remote Seal with Capillary Tubing Transmitter

The DP transmitter is located 5 feet above the bottom of the vessel and has a remote seal with capillary tubing whose fill fluid has a specific gravity of 1.9.

The following storage vessel holds a liquid with a density of 60 lb/ft³.

Remote Seal with Capillary Tubing Transmitter

The desired level measurement range is 0 feet to 11 feet:

Assuming an electronic transmitter with an output range of 4 to 20 mA, and a calibration accuracy of ± 0.2% of span.

Complete the following calibration table for the transmitter.

Now, complete the following calibration table for the level indicator:

More Questions:

1. Demonstrate how to estimate numerical answers for this problem without using a calculator.

2. Suppose this vessel were enclosed at the top, and a remote-sealed compensating leg connected from the transmitter’s “L” port to the top of the vessel. How would this change the transmitter’s necessary calibration? Would it require an adjustment in zero, span, linearity, or some combination of these?

3. Given a 100% full vessel, calculate the amount of pressure that would be registered by a pressure gauge connected to the bottom of the vessel.

4. Given a 100% full vessel, calculate the amount of pressure that would be registered by a pressure gauge connected to the capillary tube (at the remote seal).

5. Given a 100% full vessel, calculate the amount of pressure that would be registered by a pressure gauge connected to the capillary tube (at the transmitter “H” port).

Share your answers and explanation with us through the below comments section.

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Credits: Tony R. Kuphaldt