# Temperature rise in the Inductor?

#### Manjesh Gowda

Joined Oct 19, 2020
88
Hey,
I have a customized inductor which is of E70 core. I would like to calculate the temperature rise in the inductor considering ambient temperature as 30degree celcius. I have a losses around 80W, core loss=20W, Ac copper loss= 60W. I would like to calculate the maximum temperature in the core with 80W. Please let me know if anyone come across this, any link/literature would be great too. Thank you. Link for the datasheet

https://www.tdk-electronics.tdk.com/inf/80/db/fer/e_70_33_32.pdf

#### Deleted member 115935

Joined Dec 31, 1969
0
I would say as a first go,

If your dissipating 80 watts, that core at 65 by 46 by 52mm is going to get HOT

As you have wound it yourself, there is no thermal performance characteristics in the data provided,
but as the performance is quoted up to 100 degrees C, I'd say that is a god point to start

#### Manjesh Gowda

Joined Oct 19, 2020
88
I would say as a first go,

If your dissipating 80 watts, that core at 65 by 46 by 52mm is going to get HOT

As you have wound it yourself, there is no thermal performance characteristics in the data provided,
but as the performance is quoted up to 100 degrees C, I'd say that is a god point to start
I am using core E70/33/32

#### kubeek

Joined Sep 20, 2005
5,772
Hey, I have checked it. Is it just for core loss or the total loss? Do you have a clue?
I think that this depends on how you wind the bobbin and how much of the coil heat transfers into the core. I would look at it as a heat dissipation for the core, but with unknown additional heat coming from the coil, and that could be say 60-80% of the copper losses

#### Deleted member 115935

Joined Dec 31, 1969
0
You say your dissipating 80 watts

Take step back,

This is a 1 degree C per Watt heat sink, its 140 by 120 mm
https://www.digikey.co.uk/product-detail/en/apex-microtechnology/HS18/598-1474-ND/1762110

With this heat sink if you could use it,
watts would raise the temperature to 80 degrees above ambient
assume 20 ambient, that's a water boiling 100 degrees.

The bobbin on its own, is a lot worse at dissipating heat than the heat sink,
QED, your coil is going to get VERY hot VERY quickly,

Remember, when the magic smoke that powers electronics escapes, electronics stops.