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Enhanced Electronic Remote Sensor DP Level Measurement

There are many technologies to measure the level in tanks and vessels. Differential pressure (DP) is one of the tried and true methods for many applications. DP level measurement technology comprise about 30% of the total level measurement market.

Douglas Carlson and Andrew BronczykEmerson’s Douglas Carlson and Andrew Bronczyk presented on Electronic Remote Sensor (ERS) that expand the types of applications where DP level technology can be applied. Traditionallly, impulse lines are used to connect a pressure tap from the vessel to the DP device. These lines are both wet and dry. With the Rosemount ERS technology the devices are connected at the pressure tap and communicate electronically with one another, avoiding the time lags found in impulse line installations. For cold climates, removing impulse lines also means additional heating from heat trace systems is no longer required.

Andy described enhancements to the Rosemount ERS system which creates a quick look up table to determine fit for the application based on the sensor type, differential pressure range. Prior to these enhancements the user would have to provide all the operating data associated with the application and engage a specialist to determine the fit. This process could take several days.

Some additional capabilities with enhanced ERS is the addition of in-line level flanges, ideal for water level measurement applications. More challenging applications require seals which support a wider range of temperatures, sizes and corrosive environments. With a Thermal Range Expander, the temperature range goes up to 770 degF.

The cable length between the sensors has been expanded up to 500 feet. One example where this length might be required is a spherical vessel with stairs where the cable must be affixed to the sphere to traverse the distance between the two sensors.

Are you using DP level measurement with dry leg or wet leg impulse lines? If so what maintenance challenges have you seen or replaced with Rosemount ERS level measurement technology.