- General Details
The A21 gas sampling systems use a high quality diaphragm pump that is operated by a brushless DC motor to provide continuous sampling over long periods of time. Gas sampling pumps are rated for over 10,000 hours of continuous operation, and diaphragms in the pump may be changed easily if necessary. The pump will draw gas samples against a vacuum of up to 10” Hg. For sampling negative pressure duct systems when necessary.
In addition to the sampling pump, the A21 systems contain various components needed to insure reliable gas sample measurement. A flowmeter mounted on the front panel allows the user to adjust the gas sample flowrate to the desired value, normally around 500 cc./min. Internal to the system is a “loss of flow” detector that will warn of sampling system problems that could compromise the gas measurement system. A “loss of flow” alarm light on the front panel provides local flow loss indication while an internal relay can be used to indicate this alarm remotely.