Heating elements give off (power * time) joules of energy. power = potential * current so energy = potential * current * time therefore: joules = volts * amps * seconds The energy has to go somewhere, and it only comes out as heat. It is no less efficient at 120v than it is at 240v. Any inefficiency occcurs in the wires leading to the element, where any heat produced does get wasted.
-- -- Martin Klingensmith http://infoarchive.net/ http://nnytech.net/ Greg and April wrote: >Actually it kind of makes sense, If you run 120 volts through a light bulb >made for a 130 volts, they are dimmer and cooler than a 120 volt light bulb of >the same wattage, despite the fact that you are using the same amount of >electricity. It would make sense then if you are running a 120 volts, >through a 240 volt heating element, then it is going to take more electricity >to produce the same amount of heat. Heating elements are designed to give >off X amount of heat with Y volts, if you have to much voltage, you run the >risk of melting the element, with to little, it does not heat as much, I would >be willing to bet, the amount of heat is less on a per volt or watt basis than >if it was used at it's proper voltage. > >This would be easy to show if it is true or not, with two pieces of nichrome >wire of major different thickness, all you would have to do is measure how >long it would take to raise the temp of a given amount of water a given number >of degrees, for given voltages. If the thicker wire takes longer with the >lower voltage, then it would show an inefficiency. > >I'm thinking that it would take longer to heat the water, and that entire time >the water would be loosing heat to the outside, in a way it would mean >applying more heat to raise the temp the same amount. This is the basics of >melting metal, you apply the heat faster than it can be gotten rid of, so it >melts. In theory, with a perfect insulator, you could melt metal with the >heat of a candle ( an extremely large candle, I'll grant you ), because the >metal would not be able to get rid of the heat. > >Greg H. > ----- Original Message ----- > From: Martin Klingensmith > To: biofuel@yahoogroups.com > Sent: Saturday, November 22, 2003 11:34 > Subject: heating elements was Re: [biofuel] pumps, etc. > > > Dan Maker wrote: > > >Wynn said: > > > > > >>Dan, > >>Can you explain WHY "it would make an electrician shudder"? I see > >>nothing wrong with it! > >> > >> > > > >As I'm not an electrician, I am only relating what my co-worker, who is > >an electrician, said when I mentioned this to him. > > > >His biggest concern was that it was quite inefficent. For each watt used > >at 120v in a 240v heating element, a higher percentage of it is wasted than > >if you were to use the 240v element at 240v, or, and this is my own guess, > >to use a 120v element instead. But he didn't think using the 240v element > >at 120v was a very good idea. > > > >Ask someone else for a second opinion if you don't like what I'm relating > >to you. It won't hurt my feelings. After all, this is basicly my opinion > >and it's worth what you've paid for it. Absolutly nothing :) As others > >on the list have indicated, it does work. > > > >Dan > > > > > I'm not sure where this is coming from. As long as your wiring is > properly sized to the heating element, a heating element cannot be much > less than 100% efficient. > > -- > -- > Martin Klingensmith > http://infoarchive.net/ > http://nnytech.net/ > > > > > Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://archive.nnytech.net/index.php?list=biofuel Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
