Resistor Current rating

D25K20RE this is power resistor i ant to find the current capability of this resistor please help

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Hello,
Welcome to the Digikey tech forum. The datasheet does not list a current rating but can be calculated depending on the voltage. Power(watts) = I (current) x V (voltage) . In this case the power is listed at 25 watts so depending on your voltage value you can calculate the current.

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P = I2 * R

I2 = P / R

I = sqrt(P / R)

I = sqrt(25W / 10 Ohm) = sqrt(2.5) = 1.58 A

However, pay special attention to this specification in power resistor data sheets:

Power rating Based on 25°C free air rating

That means you need to remove the heat generated by the resistor from its environment very fast to prevent a rise in ambient temperature which decreases the power rating. Failure to remove the heat quickly enough can lead to thermal runaway and circuit failure.

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