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 HYDROGEN GENERATORSGenerators can also make hydrogen using one of two basic technologies: convertinganelectricaircompressortogasengine proton-exchange membranes (pem), and palladium membranes. hydrogen gas generators are most often used in convertinganelectricaircompressortogasengine gas chromatographs and in labs for hydrogenation reactions and engine-emission analysis. pem systems from parker produce flows from 90 to 1200 cc/mm of 99.99999% pure hydrogen at pressures from 0 to 100 psig. the balston h2-500 hydrogen generator uses deionized water and electricity. it produces hydrogen gas through electrolytic dissociation of water via the pem. the resultant hydrogen stream then passes through a palladium membrane for purification. because of the membrane''s small pore size, only hydrogen and its isotopes penetrate it. a membrane thus keeps the hydrogen gas at a purity level of two orders of magnitude greater than desiccant or silica gel-based systems. new compressor technology introduced during the 2003 international air-conditioning, heating, refrigerating exposition (ahr expo), held last january in chicago, may have a significant effect on the future of mid-range chillers and rooftop applications in water-cooled, evaporatively cooled, and air-cooled chilled-water and direct-expansion (dx) systems. designed and optimized to take full advantage of magnetic-bearing technology, the compressor was awarded the first ahr expo innovation convertinganelectricaircompressortogasengine and convertinganelectricaircompressortogasengine award in the energy category, as well as canada''s energy efficiency award for its potential to reduce utility-generated greenhouse-gas emissions. the compressor is key to a new water-cooled centrifugal-chiller design, with air-conditioning and refrigeration institute (ari) tests indicating integrated part-load values (iplvs) not normally seen with conventional convertinganelectricaircompressortogasengine chillers in this tonnage range. most air-cooled products (including chillers, rooftop units, and condensing units) use dx evaporators. most dx systems allow oil to travel through the refrigeration circuit and back to the compressor oil sump. great care must be taken during design to provide oil return, particularly at part load, when refrigerant flow rates are reduced.water-cooled chillers often use flooded evaporators. in a flooded evaporator, even small amounts of oil can coat evaporator tubes and significantly diminish chiller performance. this can lead to an elaborate oil-recovery system. magnetic bearings eliminate the need for these systems convertinganelectricaircompressortogasengine and oil management in general. in fact, the only required regular maintenance of the compressor is the quarterly tightening of the terminal screws, the annual blowing off of dust and cleaning of the boards, and the changing of the capacitors every five years. complete service agreements and extended maintenance contracts can be provided by the manufacturer. the use of permanent magnets instead of rotor windings makes the motor smaller and lighter than induction motors. using magnetic-bearing technology, a 75-ton compressor convertinganelectricaircompressortogasengine weighs 265 lb--about one-fifth the weight of a conventional convertinganelectricaircompressortogasengine compressor.a variable-speed convertinganelectricaircompressortogasengine drive (vsd) is required for the motor to operate. the vsd varies the frequency between 300 and 800 hz, which provides a compressor-speed range from 18,000 to 48,000 rpm. this avoids a gear set. the vsd is integrated into the compressor housing, avoiding long leads and allowing key electronic components to be refrigerant-cooled. the vsd also acts as a soft starter; convertinganelectricaircompressortogasengine as a result, the compressor has an extremely low startup in-rush current: less than 2 amps, compared with 500 to 600 amps for a traditional 75-ton, 460-v screw compressor with a cross-the-line starter. Buy a gas air compressor with us and save a TON of cash. Our selection of cheap gas air compressors is second to none.
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