☑ How To Tell The Wattage Rating Of A Resistor

You can determine a resistors wattage with a size chart. With wirewound and other power resistors the wattage rating is usually stamped on the resistor body.

Resistor Usage

Power Dissipation In Resistors In Series Versus In Parallel

Difference Between W And Ws Power Rating Of Resistors

How can you tell or measure how many watts a resistor can handle.

How to tell the wattage rating of a resistor. However the size of the resistor is a good indicator of its power rating. Lets say i salvage a few resistors from an old electronic how can i tell if its a 18 watt or 14 watt etc. Thus if a resistor has a power rating of 14 watts 14 watts is the maximum amount of power that should be fed into the resistor.

Voltagee currenti x resistancer powerp currenti x voltagee in a purely resistive circuit. How to test resistors wattage rating. In most cases physical size is a pretty good indicator of watt rating.

With carbon composition obsolete and carbon film resistors the physical size of the resistor is proportional to its wattage rating. How to calculate resistor wattage resistors can have wattage ranges that start from 003 watts to kilowatts and higher. Determine based on the schematic or with your dmm what voltage is being presented to the resistor.

On a resistor tolerance refers to the accuracy of the resistor value and is represented by a plus or minus percentage. Unfortunately you cant tell a resistors power rating just by looking at it. A 1 watt resistor will be larger than a 14 watt resistor.

Find the resistor outline on the chart that most closely matches that of the resistor itself. On a 4 band resistor the last band on the far right represents the tolerance value. Unlike resistance and tolerance there are no color codes for wattage.

Find the datasheets for a few representative resistors of various wattages and get. The measured value and ohms law will take care of the rest. The power rating of a resistor is the specification given with a resistor that serves to tell the maximum amount of power that the resistor can withstand.

The power rating of resistors can vary a lot from less than one tenth of a watt to many hundreds of watts depending upon its size construction and ambient operating temperature. Resistors can allow only a limited current amount passing through themonce the current passes through the resistor it produces heatif the heat is too great then the resistor will burn down. Most resistors have their maximum resistive power rating given for an ambient temperature of 70 o c or below.

Place the size chart see reference on a flat surface. Identify the tolerance of the resistor by finding the corresponding band. What is the power rating of a resistor.

Place the resistor on the outline to make sure they match.