Contents
Does wattage of resistor matter?
Generally speaking the larger their physical size the higher its wattage rating. When resistors with higher wattage ratings are required, wirewound resistors are generally used to dissipate the excessive heat.
How do I know what watt resistor I need?
Unfortunately, you can’t tell a resistor’s power rating just by looking at it. Unlike resistance and tolerance, there are no color codes for wattage. However, the size of the resistor is a good indicator of its power rating. Power ratings are written on the packaging when you buy new resistors.
How does wattage affect resistance?
A higher watt bulb allows more electricity through, therefore the resistance must be lower.
Is a watt equal to a joule?
Watts are defined as 1 Watt = 1 Joule per second (1W = 1 J/s) which means that 1 kW = 1000 J/s. A Watt is the amount of energy (in Joules) that an electrical device (such as a light) is burning per second that it’s running. So a 60W bulb is burning 60 Joules of energy every second you have it turned on.
What’s the average wattage of a resistor?
Resistors can range in wattage from nearly zero to… tens of thousands of watts. Without looking hard I found resistors on Digikey for sale range from .0125 to 80 watts. Wattage means how much power the physical resistor is rated to handle.
Why do we need wattage for SMD resistors?
So we tend to stick with a wattage that will suite 99% of our needs and that happens to be 1/4 watt resistors. For their physical size, these will suite most circuits without the need to calculate the wattage for every resistor and presuming we are not into SMD resistors.
Which is more important, the wattage or the resistance?
Wattage may be more importaint then resistance. Resistors can range in wattage from nearly zero to… tens of thousands of watts. Without looking hard I found resistors on Digikey for sale range from .0125 to 80 watts. Wattage means how much power the physical resistor is rated to handle.
Is it OK to use parallel resistors in a circuit?
Yes, its fine to parallel resistors to get the desired power rating. Just remember to take into account the tolerance of the resistors and the fact that they won’t share current perfectly due to this. However, as a practical matter you should be oversizing your resistors anyway so that this isn’t really a problem.