Agilent Technologies G6600-90006 manual Two-stage pressure regulators

with air as the oxidant in the SCD and oxygen as the oxidant in the NCD.

For the SCD, detector gases must be sulfur free (<1ppb) for proper Detector operation. In general, bottled air is preferred to “house” air from a compressor because compressors tend to generate lower quality air. In addition, pressure fluctuations induced by the air generator may be detrimental to Detector performance.

For the NCD and GC, use gases that are low in nitrogen and total hydrocarbons. Use gases with an "instrument" or "chromatographic" purity rating. Agilent recommends gases with a purity range of 99.995% to 99.9995%. Do not use oil-pumped supplied air since it contains large concentrations of hydrocarbons.

Use of appropriate traps on carrier, hydrogen and oxidant sources to improve support gas quality, such as a sulfur trap gas purifier, is recommended. The oxidant used to supply the ozone generator should be dry to prevent internal corrosion. Use of a moisture trap or dryer is recommended.

Two-stage pressure regulators

The combustion gases must be supplied to the Controller at a pressure of

25 psig or less. Use a two-stage pressure regulator rather than a single-stage regulator to eliminate pressure surges. High-quality, stainless-steel diaphragm-type regulators are recommended. On/Off valves at the regulators are useful but are not essential. Mount the valves at the outlet fitting of the pressure regulators.

If you use gases with a two-stage regulator up-stream, it will be sufficient to use single-stage regulators at the Detector.

Particle Filtration

Up-stream, inline particle filtration of 10 micron or better is required to prevent damage to Controller and Burner components.

WARNING	Ozone is a hazardous gas and a strong oxidant. Minimize exposure to ozone by using the
	instrument in a well-ventilated area and venting the exhaust of the vacuum pump to a
	fume hood. Turn off the ozone generator when the instrument is not in use.
	Supply Tubing for Combustion Gases
	Use preconditioned and cleaned copper or stainless steel tubing to supply
	gases to the 355 SCD and 255 NCD. Do not use ordinary copper tubing since it
	contains oils and other contaminants. Plastic tubing is not recommended since
	it is permeable to oxygen and other contaminants that can damage columns
	and detectors or cause elevated background. Teflon tubing may be acceptable
	in some clean environments.

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