Emerson Process Management 1500 Example, 10.5Performing density calibration, Sensor requirements

Measurement Performance

Example	The flowmeter is installed and proved for the first time. The flowmeter
	mass measurement is 250.27 lb; the reference device measurement is
	250 lb. A mass flow meter factor is determined as follows:
	250
	MassFlowMeterFactor = 1 ⋅ ----------------- = 0.9989
	250.27
	The first mass flow meter factor is 0.9989.
	One year later, the flowmeter is proved again. The flowmeter mass
	measurement is 250.07 lb; the reference device measurement is
	250.25 lb. A new mass flow meter factor is determined as follows:
	MassFlowMeterFactor = 0.9989 ⋅ 250.25----------------- = 0.9996
	250.07
	The new mass flow meter factor is 0.9996.

10.5Performing density calibration

Density calibration includes the following calibration points:

•All sensors:

-D1 calibration (low-density)

-D2 calibration (high-density)

•T-Series sensors only:

-D3 calibration (optional)

-D4 calibration (optional)

For T-Series sensors, the optional D3 and D4 calibrations could improve the accuracy of the density measurement. If you choose to perform the D3 and D4 calibration:

•Do not perform the D1 or D2 calibration.

•Perform D3 calibration if you have one calibrated fluid.

•Perform both D3 and D4 calibrations if you have two calibrated fluids (other than air and water).

The calibrations that you choose must be performed without interruption, in the order listed here.

Note: Before performing the calibration, record your current calibration parameters. If you are using ProLink II, you can do this by saving the current configuration to a file on the PC. If the calibration fails, restore the known values.

You can calibrate for density with ProLink II.

10.5.1Preparing for density calibration

Before beginning density calibration, review the requirements in this section.

Sensor requirements

During density calibration, the sensor must be completely filled with the calibration fluid, and flow through the sensor must be at the lowest rate allowed by your application. This is usually accomplished by closing the shutoff valve downstream from the sensor, then filling the sensor with the appropriate fluid.

Compensation

Measurement Performance

Troubleshooting

Defaults

Configuration and Use Manual 87