|
Tractor Talk Discussion Board |
Re: Electronics 101 Question .....
[ Expand ] [ View Replies ] [ Add a Reply ] [ Return to Forum ]
Posted by Gerald J. on October 25, 2006 at 19:39:57 from (67.0.102.127):
In Reply to: Re: Electronics 101 Question ..... posted by Bob/Ont on October 25, 2006 at 19:00:10:
No. The temperature rise of the resistor depends only on the cooling area of the resistor. A resistor reaches its maximum rated temperature rise with rated power dissipated. That is independent of voltage, current, or resistance. A resistor will have a temperature rise proportional to the actual power disspated times the rated temperature rise divided by the rated power. So if the dissipated power is smaller than the rated power the temperature rise will be small. If the dissipated power is larger than the rated power the temperature rise will be large and it depends on the construction of the resistor whether that resistor will smoke or will survive. Vitrious glass coated wire wound resistors on ceramic cores can take a few times rated power, but they may melt the glass and that glass dripping on adjacent objects may ignite the surroundings. Tin oxide film resistors I've found can handle ten times rated power, but they glow and the heat radiated can ignite adjacent objects like plastic cases or fiberglass-epoxy printed circuit boards. Old carbon composition resistors will smoke at not much above their rated power and will drift in resistance just from the passage of time, though heat and humidity will speed up the drift in resistance. Gerald J.
Replies:
Home
| Forums
Today's Featured Article -
Madison's County - by Anthony West. Philip Madison has been a good friend of mine for quite some time. He has patiently suffered my incessant chit chat on the subject of tractors for longer than I care to remember, and on many occasions he has put himself out, dropped what ever it was he was doing, to come and lend a hand cranking handles, or loading a find onto a trailer. Although he himself has never actually owned or restored a tractor, he was always enthusiastic and always around helping with other peoples projects.
... [Read Article]
Latest Ad:
1964 I-H 140 tractor with cultivators and sidedresser. Starts and runs good. Asking 2650. CALL RON AT 502-319-1952
[More Ads]
Copyright © 1997-2025 Yesterday's Tractor Co.
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V. Yesterday's Tractors - Antique Tractor HeadquartersWebsite Accessibility Policy |
|
