Instruction Manual

748297-E June 2003

Model NGA2000 HFID

introduced through the sample inlet at the rear of the module.

Zero Gas - Analysis is affected by the background gas of the sample. Therefore, it is recommended to use zero gas with as close to the background composition of the sample as possible. Normally less than 0.5 THC as CH4 is sufficient.

Span Gas - Span gas consists of a specified concentration of methane or other hydrocarbon in a background gas such as nitrogen. Analysis is affected by the background gas of the sample. Therefore, span gas containing the same background gas as the sample is recommended. Then, the background effect is canceled out.

h.Sample Gas Specification

Sample gas should be nonflammable (be- low 100% of the sample's LEL). For high sensitivity applications requiring background gas compensation, contact the factory.

i.Flow Rate Specification

Required sample flow rate is 1.0 L/min. to 2.5 L/min. for a supply pressure between 5 and 9 psig. Flow rate for purge gas should be 16 to 18 L/min. Flow rate for regulated air should be 2 to 4 L/min.

j.Pressure/Filtration Specification

Sample Pressure at the SAMPLE inlet should be within the range of 345 to 620 hPa-gauge (5 to 9 psig, 7.0 psig nominal), and internally, should be between 206.7 and 275.6 hPa-gauge (3.0 and 4.0 psig).

Burner Fuel Pressure should be: 3101 to 3450 hPa-gauge (45 to 50 psig) for cylinder

regulator, 1723 hPa-gauge (25 psig) nominal for internal pressure.

Burner Air Pressure should be : 1725 to 3450 hPa-gauge (25 to 50 psig) for cylinder regulator, 1035 hPa-gauge (15 psig) nominal for internal pressure.

Regulated Air Pressure should be 689 to 1725 hPa-gauge (10 to 25 psig) for cylinder regulator.

Purge Air Pressure should be 689 to 1380 hPa-gauge (10 to 20 psig).

Nominal Internal Case Pressure is about 0.5 to 1.0 inch of water, and the pressure relief valve is set at 1/3 psig (nominal).

CAUTION

OVER-PRESSURE

Noncompliance with these specifica- tions, particularly those concerning purge air, could cause over-pressure damage to the module.

Note

The sample gas and regulated air should be filtered for particulates down to 2 microns to prevent the plugging of pneumatic components.

k.Leak Test

The analyzer module is completely leak tested at the factory. The user is re- sponsible for testing for leakage at the inlet and outlet fittings on the rear panel. The user is also responsible for internal leak testing periodically and if any inter- nal pneumatic components are adjusted or replaced (with a test procedure cho- sen by the user).

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Installation

Rosemount Analytical Inc. A Division of Emerson Process Management