I have a DLC3010-249B measuring interface of water and condensate (SG about .6) on a waterboot. The displacer is 14 inches long and the transmitter is scaled 0-14".
Operator notified us that it is reading incorrectly. In their opinion it was reading a water level when it is only condensate.
I isolated and drained the chamber and the level indication went -20 inches. I was able to Zero trim it to 0, very surprised.
I was then able to do the 2 point calibration, floating the displacer in clean water.
The transmitter was put back in service and returned to operation. Although is seems to be working better, they believe the water is 0% while the interface is still reading 65%. They are basing their assumption on the rise in line pressure as the condensate starts to flow. Which is a reasonable assumption.
Is it possible, or would this be a reasonable characteristic, of the displacer loosing its calibrated weight?
DLC3010.pdf
Did you change back to interface after the two point calibration with water? From the Quick Start Guide (which I tried to attach): For an interface application—Change PV mode procedure, and then use 'Enter constant SG' to configure the instrument for the SGs of each of the target process fluids.
I don't work much with displacers, so not sure this is helpful.
Thanks Lydia.
Dwade, based on your description when the chamber is drained, the level is indicating -20in. This is correct.
The application you are having is an interface application. The upper fluid being the condensate (0.6 SGU) and the lower fluid being the water (~1 SGU).
Per attached image, I listed down the level measurement you should observe when DLC3010 is calibrated correctly.
The operator mentioned the reading was incorrect as they thing the DLC3010 was reading a water level when it is only condensate. Do you know what was the reading?
I am guessing the scenario that operator experienced was the chamber was occupied with condensate and air (there could be water as well), which we called a double interface.
Displacer technology will not be able to measure double interface. For it to work properly (0%-100%), the displacer must always be covered by either fluids. Where the 3rd fluid occurred (air), the displacer experiences double interface, and DLC3010 will not be able to measure correctly.
Since you have calibrated the DLC3010 with clean water, I assumed that you calibrated with the below setting:
PV = Level
Density = 1 SGU
This calibration will calculate the correct torque tube rate for the 249B.
Once the above calibration is done, you will need to switch the settings to below:
PV = Interface
Upper Fluid = 0.6 SGU
Lower Fluid = 1 SGU
When the actual process fluid flow into the chamber, you will need to run Trim Zero to tell the DLC3010 what is the actual measurement. Take note that this Trim Zero must be run within 0-100% of the interface. It cannot be run when there is a double interface as DLC3010 will not work in double interface.