picking an NTC thermistor for current inrush limiting

[ledtester]

I have a a PowerOne HD28-4-AG (28V, 4A) open frame linear power supply which has a 13000 uF filtering capacitor, and I'd like to use a NTC thermistor to limit the inrush current.

On Digikey the main parameters for NTC thermistors are R@25C, Steady State Current and R@Current.

I guess my Steady State Current doesn't need to be more than 2A (I live in the US), but how would you go about choosing the values for R@25C and R@Current?

Thanks!

[Quarlo Klobrigney]

Check https://www.mouser.com/Circuit-Protection/Thermistors/Inrush-Current-Limiters/_/N-axfxj/ for your specs. If it's no help, check back.

[ocset]

just check it doesnt overheat at the "R at current".
Ie, that the NTC can handle your steady state current.
The great thing about NTCs that can handle the steady state current, is that they wont blow up from  almost any amount of inrush....because they will just heat up and then effectively cool themselves down by reducing their resistance....unlike a resistor which may blow.

[Gyro]

The great thing about NTCs that can handle the steady state current, is that they wont blow up from  almost any amount of inrush....because they will just heat up and then effectively cool themselves down by reducing their resistance....unlike a resistor which may blow.

Unless you power cycle them quickly and they haven't had time to cool down. Then the excessive inrush current into a substantial load can easily kill them.