Emerson 2200S Pacemaker User Manual


 
Configuration and Use Manual 95
Operation AppendicesMaintenance and TroubleshootingCommissioning
Chapter 9
Measurement Performance
9.1 Overview
This chapter describes the following procedures:
Meter validation and adjusting meter factors – see Section 9.3
Density calibration – see Section 9.4
Temperature calibration – see Section 9.5
Before performing the procedures in this chapter, make an administrative connection to the transmitter
and ensure that you are complying with all applicable safety requirements.
9.2 Meter validation and calibration
The Model 2200S transmitter supports the following procedures for the evaluation and adjustment of
measurement performance:
Meter validation – confirming performance by comparing the sensor’s measurements to a
primary standard
Calibration – establishing the relationship between a process variable (flow, density, or
temperature) and the signal produced by the sensor
These procedures are discussed and compared in Sections 9.2.2 and 9.2.3. Before performing any of
these procedures, review these sections to ensure that you will be performing the appropriate
procedure for your purposes.
9.2.1 Meter validation and meter factors
Meter validation compares a measurement value reported by the transmitter with an external
measurement standard. Meter validation requires one data point.
Note: For meter validation to be useful, the external measurement standard must be more accurate
than the sensor. See the sensor’s product data sheet for its accuracy specification.
If the transmitter’s mass flow, volume flow, or density measurement is significantly different from the
external measurement standard, you may want to adjust the corresponding meter factor. A meter
factor is the value by which the transmitter multiplies the process variable value. The default meter
factors are 1.0, resulting in no difference between the data retrieved from the sensor and the data
reported externally.
Meter factors are typically used for proving the flowmeter against a Weights & Measures standard.
You may need to calculate and adjust meter factors periodically to comply with regulations.