The A21 is a gas sample pumping system designed to draw samples from ducts or hard to access locations and deliver the samples to gas sensors located in a more convenient area.
The A21 is a gas sample pumping system designed to draw samples from ducts or hard to access locations and deliver the samples to gas sensors located in a more convenient area. A21 Sampling Systems use a high quality diaphragm pump operated by a brushless DC motor to provide continuous sampling over long periods of time. 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 samples against a vacuum of up to 10" Hg. for sampling negative pressure duct systems when necessary.
In addition to the sampling pump, A21 systems contain various components needed to insure reliable sample measurement. A flowmeter mounted on the front panel allows the user to adjust the 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.
|Image||Part #||Product Description||Price||Stock||Order|
|00-0703||A21 inlet filter assembly||Drop ships from manufacturer|
For decades, commercial fishing for yellow perch was allowed in southern Lake Michigan. This persisted until 1996 when it was outlawed, giving perch stocks there some time to recover. Scientists had for some time assumed that this fishing ban would not affect the reproduction cycles of the perch quickly and that they were going to need a long time to revert back to the cycles they relied on before commercial fishing ever started. But new research led by scientists at Purdue University finds that maturation schedules of yellow perch in southern Lake Michigan are much more resilient than had been previously thought possible.Read More
Largely seen as pristine and relatively untouched by human activity thanks to its protected status, the portion of the Colorado River flowing through Grand Canyon National Park is anything but, according to recently published research. This is evidenced by high levels of selenium and mercury found in the fishes there. Scientists from many institutions were involved in the years-long work, full results of which have been published in the journal Environmental Toxicology and Chemistry. It was led by the U.S. Geological Survey, but perhaps the contributors from Idaho State University got the best end of the stick. They were looking into the food webs of the river to evaluate concentrations of selenium and mercury gathering in fish.Read More
For all the straightforward groundwater monitoring applications that the folks at Heron Instruments help with, there are a few that are far from typical. These include projects that take place near remediation sites or not far from waste disposal operations. Realizing that customers working in those sorts of projects are in need of a more robust option, the company has released the dipper-Tough . The new water level meter takes inspiration from Heron’s popular dipper-T , while throwing in a host of improvements that environmental pros working in groundwater can really appreciate.Read More