Dec 21, 2009 #1 S sathishdn Newbie level 4 Joined Dec 10, 2009 Messages 6 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Location Bangalore Activity points 1,330 how to decide the wattage of the resistor
Dec 21, 2009 #2 elec4fun Full Member level 3 Joined Jan 24, 2005 Messages 159 Helped 38 Reputation 76 Reaction score 31 Trophy points 1,308 Location Nice, France Activity points 897 Hello, What about P=UI or P=RI² ? It was a pleasure to help a so polite person... Best regards.
Dec 21, 2009 #3 flatulent Advanced Member level 6 Joined Jul 19, 2002 Messages 4,624 Helped 489 Reputation 980 Reaction score 151 Trophy points 1,343 Location Middle Earth Activity points 46,689 The manufacturer's data sheet is the first place to look. Make sure that you understand the environment that the rating is for. One example is free circulating air. Another is the trace width and thickness that it is connected to.
The manufacturer's data sheet is the first place to look. Make sure that you understand the environment that the rating is for. One example is free circulating air. Another is the trace width and thickness that it is connected to.
Dec 21, 2009 #4 L leonzam Newbie level 6 Joined Nov 14, 2004 Messages 13 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 93 NASA recommends Max. of 60% of rated power (see attached file) Ian Sinclair recommends in his book Passive Components for Circuit Design to keep resistors temperature below 70 Degree celcius see aprox temp rise in a resitor
NASA recommends Max. of 60% of rated power (see attached file) Ian Sinclair recommends in his book Passive Components for Circuit Design to keep resistors temperature below 70 Degree celcius see aprox temp rise in a resitor
Dec 31, 2009 #5 P praveensss Junior Member level 2 Joined Dec 31, 2009 Messages 24 Helped 2 Reputation 4 Reaction score 1 Trophy points 1,283 Location Bangalore Activity points 1,401 check the voltage across the resistor. W = V * V * R. Take a safety factor of atleast 1.5 - 2, if the resistor has to run cool.
check the voltage across the resistor. W = V * V * R. Take a safety factor of atleast 1.5 - 2, if the resistor has to run cool.