How hot is too hot for a resistor?

According to a Yaego datasheet for metal film resistors, resistors can be operated at 100% of their rated load at an ambient temperature of 70C or lower. You don’t need to derate to 50% until ambient temperature is over 100C.

How much heat can a resistor take?

The resistor is dissipating 400 mW, so its temperature rise will be about (400 mW)(200 °C/W) = 80 °C. If it’s on a open board on your desk, you can probably figure 25 °C maximum ambient, so the resistor could get to 105 °C. Note that’s hot enough to boil water, but most resistors will be fine at this temperature.

What happens if my resistor is too high?

When electricity is conducted through a resistor, heat is generated and dissipated through the surrounding air. Under excessive voltage, a resistor generates so much heat that it cannot dissipate the heat quickly enough to prevent burning.

What should the temp of a 10W resistor be?

But, if you follow the 10W curve over to 25C (about room temperautre), the resistor should be able to handle 100% of it’s rated power. Note that I’m only assuming the ambient temperature is 25C! If you have it lying on a brick, it should be okay. It appears that the resistor can handle up to about 115C ambient temp @ 65% load.

Why is my resistor getting hot with only 6.5w?

The ohm rating is 220 ohms, which is correct for the circuit ohms which is calculated to about 225 ohms. Within a couple minutes it got so hot that it burned me. I’m ok though because I only touched it for a second. But I was expecting it to stay cool since the resistor is rated at almost double the power that is going through it.

What makes a resistor have a good power rating?

The wattage rating relies on the dimension of the resistor also. The power dissipation starts with heat rise in temperature and the wattage also increases. For higher voltage applications, power wire wound resistors have a good power rating and they are specially designed to work at temperatures above 300°C for a shorter period of time.

What’s the power rating of a wire wound resistor?

For higher voltage applications, power wire wound resistors have a good power rating and they are specially designed to work at temperatures above 300°C for a shorter period of time.