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Inrush current burns switches

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just5554:
Good day, I have a problem with switches. I'm using push lockable illuminated switches. The problem is, when I turn on DPS5005 power unit, there is huge inrush current, that welds contacts. I've tried few switches, both failed after few attempts to turn on.

Video showing how it welds itself: https://drive.google.com/file/d/1-OyGRqnLu5fEOEtO4Wsgc-eF1KHVMxBO/view?usp=sharing

My question is: how to avoid this? (Besides installing not pushable switch) I'm not very keen to install mains voltage switch to switch power supply. 

Gyro:
I'm not really familiar with the DPS5005 but it looks as if you have two problems...

1. The magnitude of the inrush current due to capacitors and load.
2. DC current is notoriously difficult to break.

Contact welding is clearly a number 1 problem (although contact bounce brings number 2 in too).

Your easiest approach is going to be to use the switch to drive a 42V (48V more common) relay with appropriately rated high current contacts. Use a snubber (100R in series with 100nF) across the switch contacts to reduce residual arcing.

A more expensive approach would be to use a DC solid state relay instead of a mechanical one.

wraper:
It's not appropriate to use switch there. You have high capacitance on the output of SMPS, and high capacitance on the input of DPS5005. The result is that you basically short cap in SMPS thorough that poor switch. You need inrush current limiting, simply using a switch is not a good idea. And why would you need it there to begin with? You should switch SMPS on the mains side, not between PSUs.

just5554:
Thank you for your ideas. I think the best solution would be to buy same switch but rated for 220v and use it to switch whole unit. Although I do not like puting components ordered from china on mains voltages. But oh well, what could go wrong besides current leak to metal enclosure... :-X

duak:
It will be difficult to find a switch or even a relay that will not weld closed - the current is so high.

I would not try to use the pushbutton to switch the 42 VDC current, instead I would switch the AC into the supply or control the 42 V supply directly.  Is the 42 V supply from a server?  These supplies usually have some sort of on/off control input.

If I really had to switch the 42 VDC current, I would use a power transistor large enough for the current and switch the base current of the transistor.  If you provide information on the power supply, switch, and the value of the capacitor on the input of the DPS5005, I can give more help.

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