Please explain ABB 266MRT, 266GRT and 266ART Pressure transmitters with seals (DP).how to calibrate as a level transmitter? And , is there a need of zero suppression in this model?

 

Only the MRT model, DP technology, is used for dual remote seals for level. GRT is gauge pressure and ART is absolute pressure, neither of which is suitable for dual remote seals for level measurement.

The document you reference is a spec sheet that does not have installation information on calculating the LRV and URV for level applications, which requires knowing the Specific Gravity of the fill fluis, the Specific Gravity of the measured medium, and the elevation of the low side seal above the datum of the high side seal at the bottom. I could not find that information in a quick review of the ABB 266MRT HART installation manual, either.

The calculation is the same for all remote seal DP transmitters, regardless of manufacturer, so I will refer you to Honeywell's remote seal spec sheet that provides the calculation for LRV and URV for dual remote seals.

see page 23 in the document at this link:
https://www.honeywellprocess.com/library/marketing/tech-specs/34-ST-03-104.pdf

Note that an LRV value in a dual remote seal application is typically a very large negative value due to the hydrostratic pressure of the fill fluid in the capillaries when the vessel is empty. The URV is typically also a negative value, but a value closer much closer to zero.