Smart Meter Verification Enhancements Improve Safety and Process Availability
November 17, 2009
At Emerson Exchange 2009, Emerson presented Smart Meter Verification Enhancements Improve Safety and Process Availability, a paper that began by defining terms. 
- Calibration is performed at the factory. It establishes the relationship between flow and signal produced by the sensor.
- Validation confirms flow performance by comparing a primary flow standard to the sensor.
- Verification establishes confidence in performance by analysis of the secondary variables associated with flow.
Many times these terms are used interchangeably. Also, frequently calibration or validation is done when only verification is needed.
During factory calibration, baseline measurements are performed in which the smart device can self-check against ones operating in the field. For example, Micro Motion Coriolis meters check tube stiffness and Rosemount E-series magnetic flowmeters check against a magnetic field signature to perform ongoing verification.
Smart Meter Verification is verification either on demand or on a schedule. It provides whole-system diagnosis, including the sensor, drive, and signal processing. This verification process provides absolute confidence in measurement performance and is recognized in Alberta by the ERCB as being compliant with Directive 17, Section 2.6 for liquid meters.
Benefits of Emerson’s SMART Meter Verification include:
- Reduced maintenance costs
- Improved availability
- Improved Safety, Health & Environment
- Improved quality
- Reduced waste & rework
Specific cases:
With Micro Motion Coriolis SMART Meter Verification, the Coriolis meter has no moving parts. Coating and corrosion can impact the stiffness of the meter tubes. SMART Meter Verification measures the meter's mechanical characteristics so that when a change in the tube stiffness is detected, performance is checked to see if it remains within factory specifications.
Rosemount magnetic flowmeters also have no moving parts and have an expectation that the meter calibration will never change. Over time, the calibration may be impacted if there is a shift in the coils due to vibration, thermal cycling, etc. SMART Meter Verification measures the sensor's magnetic field strength characteristics, and when a change is detected, it determines whether the meter's performance remains within factory specifications.
For the Rosemount 8800 Vortex flowmeter, the vortex sensor is a piezo crystal, which provides a low-level voltage when flexed. Vortices in the flow cause the sensor to pulse. The vortex electronics take the frequency of these pulses to deliver a flow output.
Historically, vortex meter verification has been difficult. It's become easier since properly functioning electronics can be verified by testing with a known frequency. The vortex sensor can be verified by measuring signal strength with a handheld device or via applications, such as AMS Device Manager software.