Optional Configuration

Only one type of volume flow measurement can be performed at a time (i.e., if liquid volume flow measurement is enabled, gas standard volume flow measurement is disabled, and vice versa). Different sets of volume flow measurement units are available, depending on which type of volume flow measurement is enabled (see Tables 6-3and 6-4). If you will use a gas standard volume flow unit, additional configuration is required.

Note: If you will use the petroleum measurement application or the enhanced density application, liquid volume flow measurement is required.

The method used to configure volume flow measurement for gas depends on the tool you are using: ProLink II or a DeviceNet tool.

Note: For complete configuration of volume flow measurement for gas, you must use either ProLink II or a DeviceNet tool. Using the display, you can only select a volume measurement unit from the set available for the configured volume flow type.

8.2.1Using ProLink II

To configure volume flow measurement for gas using ProLink II:

1.Click ProLink > Configure > Flow.

2.Set Vol Flow Type to Std Gas Volume.

3.Select the measurement unit you want to use from the Std Gas Vol Flow Units dropdown list. The default is SCFM.

4.Configure the Std Gas Vol Flow Cutoff (see Section 8.3). The default is 0.

5.If you know the standard density of the gas that you are measuring, enter it in the Std Gas Density field. If you do not know the standard density, you can use the Gas Wizard. See the following section.

Note: The term “standard density” refers to the density of the gas at reference conditions.

Using the Gas Wizard

The Gas Wizard is used to calculate the standard density of the gas that you are measuring.

To use the Gas Wizard:

1.Click ProLink > Configure > Flow.

2.Click the Gas Wizard button.

3.If your gas is listed in the Choose Gas dropdown list:

a.Enable the Choose Gas radio button.

b.Select your gas.

4.If your gas is not listed, you must describe its properties.

a.Enable the Enter Other Gas Property radio button.

b.Enable the method that you will use to describe its properties: Molecular Weight,

Specific Gravity Compared to Air, or Density.

c.Provide the required information. Note that if you selected Density, you must enter the value in the configured density units and you must provide the temperature and pressure at which the density value was determined.

Note: Ensure that the values you enter are correct, and that fluid composition is stable. If either of these conditions is not met, gas flow measurement accuracy will be degraded.

Using a DeviceNet Tool

Required Configuration

Using the Transmitter

Optional Configuration

Configuration and Use Manual

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Emerson Process Management 2400S manual Using the Gas Wizard, Click ProLink Configure Flow