{"id":11182,"date":"2016-11-19T15:40:00","date_gmt":"2016-11-19T22:40:00","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=11182"},"modified":"2016-11-19T15:40:00","modified_gmt":"2016-11-19T22:40:00","slug":"a-24-volt-airplane-motor","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/a-24-volt-airplane-motor\/","title":{"rendered":"A 24-Volt Airplane Motor?"},"content":{"rendered":"

One of the big surprises in last month\u2019s webinar hosted by the EAA and presented by Brian Carpenter of Rainbow Aviation Services\/Adventure Aviation was the 24-Volt motor being developed for the EMG-6 ultralight motorglider<\/a>.<\/p>\n

\"EMG-6

EMG-6 in side view with electric powerplant – still Part 103 legal, according to Brian Carpenter<\/p><\/div>\n

High and Low Voltages<\/strong><\/p>\n

Many, if not most of the electric motors flying on existing craft are higher voltage units.\u00a0 For sake of an off-handed definition, we\u2019ll divide low and high at below and above 50 Volts, something OSHA delineates in its regulation 29 CFR 1910.303(g)(2)(i), which \u201cgenerally requires “\u2019live parts of electric equipment operating at 50 volts or more\u2019 to be \u2018guarded against accidental contact by use of approved cabinets or other forms of approved enclosures\u2019 or by other specified means.\u201d\u00a0 In its explanation, the Occupational Safety and Health Administration<\/a> \u201cconsiders all <\/em>voltages of 50 volts or above to be hazardous. Electric current, not voltage, passing through the human body causes injury\u2026.\u201d<\/p>\n

And it really doesn\u2019t take much amperage to take a person to the next realm.\u00a0 Electric chairs, for instance, pass voltages from 500 to 20,000 Volts through the condemned\u2019s body, but at currents of only five to 20 Amperes.\u00a0 Shockingly, “A current of 0.070\u00a0ampere causes heart problems<\/a> and may be fatal.”\u00a0 The lesson is that all electric devices need to be treated with caution and respect.<\/p>\n

While high power in aircraft electric motors comes from a combination of high voltages and high amperages (multiply the two to get the kilowatt output of the motor), Roman Susnik and EMRAX provide three voltage levels with correspondingly varied amperages to suit motors to different applications.<\/p>\n

https:\/\/www.youtube.com\/watch?v=-e_wmSA3Mos<\/p>\n

The Emrax 228, for instance, can be ordered in high, medium and low voltage configurations.\u00a0 The high-voltage version can handle up to 600 Volts at a maximum current of 240 Amps.\u00a0 The low-voltage model can run on 24 to 150 Volts, but at 900 maximum Amps.\u00a0 Because the resulting torque is so great from especially the low-voltage motors, they can swing large propellers at low RPMs while providing significant thrust. \u00a0Certainly the early demonstration of low-speed torque shows low noise and an undocumented level of thrust at 450 RPM. \u00a0Most Emrax motors don’t exceed 2,200 RPM at full power.<\/p>\n

A 48-Volt Automobile<\/strong><\/h4>\n

A European car manufacturer, NanoFlowCell, produces two vehicles, the Quant F and Quantino, powered by liquid flow cell batteries.\u00a0 The Quantino has four wheel-hub type 48-Volt motors, each capable of producing 200 Newton-meters (147.5 foot-pounds) of maximum torque.\u00a0 We\u2019ve covered the Quant in an earlier post.<\/p>\n

This 48-Volt car ran 14 hours on a very level, smooth floor and still had 78-percent of the energy stored in its two 159-liter (84 gallons) tanks available, according to the company.\u00a0 This demonstration, while impressive, is somewhat like Sanyo\u2019s battery-powered six-year-old, 1,000 kilometer run without a recharge.\u00a0 Run at 25 mph, Sanyo\u2019s record was not a big challenge<\/a> for even the draggiest vehicle.\u00a0 It\u2019s unlikely the Quantino went much faster, considering the confined quarters.<\/p>\n

Salt water weighs about 8.5 pounds per gallon, so the Quantino is lugging around 714 pounds of motive power.\u00a0 It has the same issue that batteries have, not diminishing in weight as the energy burns off.\u00a0 Any car or airplane using either energy storage medium ends its journey as heavy as when it started.<\/p>\n