I am debugging a machine, input 220VAC, and convert it into 24V through the built-in power supply to supply power to the main control board. When the surge hits the common mode L-PE 2000V, the main control board freezes and does not work. It can be restored after shutdown. There is no problem when the common mode is at 1000V. What is the reason? Is there any solution? ?
Hi Martin,
While some of our parts are rated for that use, we recommend that those decisions are made by qualified technicians that are licensed to work with mains power. That goes for the work itself, it is a legal requirement anyhow.
To wrap-up: Mains power isn’t just lethal. It’s lethal.
Stay safe & keep to low voltage projects. Or employ a contractor to help.
Thank you for your suggestion, I know and will stay safe.
No worries Martin,
As well as being extremely dangerous, breaching the ASNZS3000 and similar wiring laws can put you at liability if something goes wrong. Of course, the forum isn’t the place to go for legal advice 
or to discuss projects above ELV if you are licenced. It’d be an excellent idea to ask a local licenced sparky for help. All the best with your project!
