Energy Sources
Currently an electric motor is the most popular choice to power stationary tools, though in the past they were powered by windmills, water wheels and steam. Some museums and hobbyists still maintain and operate stationary tools powered these older power sources. Portable electric tools may be either corded or battery-powered. Compressed air is the customary power source for nailers and paint sprayers. A few tools (called powder-actuated tools) are powered by explosive cartridges. Tools that run on gasoline or gasoline-oil mixes are made for outdoor use; typical examples include most chainsaws and string trimmers. Other tools like blowtorches will burn their fuel externally to generate heat. Compressed air is universally used where there is a possibility of fuel or vapor ignition - such as automotive workshops. Professional level electric tools differ from DIY or 'consumer' tools by being double insulated and not earthed - in fact they must not be earthed for safety reasons.
Read more about this topic: Power Tool
Famous quotes containing the words energy and/or sources:
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—Stefan Zweig (18811942)
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—Barbara Ehrenreich (20th century)