AC relay contacts welded by inrush current to capacitors

Hello,
i have one of those AC motion sensors that are powered directly from 230V mains and provide switched AC phase output. I've connected 12V/6A (notebook-like) PSU to it to power 12V/3A LED stripes.

However it seems that relay contacts get welded together from time to time. (It does not switch off until i punch the motion sensor box to make contacts fall apart). So i suppose that's because of some filter capacitors on input of that 12V supply are causing inrush current thru relay. Motion sensor was probably designed for lightbulbs and ccfls so it cannot handle this properly.

Is there some way to limit this inrush current to keep relay contacts safe? I suppose there's already NTC thermisor for inrush current limiting in the supply.


BTW i've found this on internet, however i don't understand how it should help. It probably can only add more current to inrush as it adds another capacitor:



[from: www . industrologic . com/mechrelay.gif]

I suppose there's already NTC thermistor for inrush current limiting in the supply.

Click to expand...

Your results are suggesting it's not.

I've found this on internet, however i don't understand how it should help.

Click to expand...

It's not related to inrush current protection.

Inrush current limiting is a very common practice in higher powered circuits.

Ametherm and others make NTC thermistors specifically designed to quench inrush currents.
There is a good tutorial on the web:

https://www.digikey.com/en/ptm/a/am...al?WT.srch=1&gclid=CJPx9Y7K_c4CFceVGwod8VQCUA

I've installed some MF71 NTC scavenged from ATX PSU, so i'll see...