hi Hymie,
The TS had an earlier thread relating to these mounting holes.

https://forum.allaboutcircuits.com/threads/where-how-to-connect-mounting-pads.150102/
Eric
EDIT: Added the Thread link.

 

You also appear to be using the PCB mounting points for earth connections, which is not good practice due to the PCB insulation within the earth connection.

I'm sorry, could you please elaborate on this statement? The mounting pads are not connected to earth, but to pcb ground plane. Screws will be mounted to a plastic container, not to metallic earthed container. The idea was to not leave any metal parts within the container floating.

Thanks

 

I'm sorry, could you please elaborate on this statement? The mounting pads are not connected to earth, but to pcb ground plane. Screws will be mounted to a plastic container, not to metallic earthed container. The idea was to not leave any metal parts within the container floating.

Thanks

‘Ground’ and ‘earth’ are interchangeable in terms of their meaning – it more common for our American cousins to use the term ground, whereas within Europe earth is the norm.

You are using the term to indicate the 0V of the secondary supply – which is not connected to ground/earth; therefore to avoid confusion I would recommend you change the ‘GND’ legend on the PCB to 0V.

You need to ensure that this 0V track is separated from mains by at least 5mm.

 

‘Ground’ and ‘earth’ are interchangeable in terms of their meaning – it more common for our American cousins to use the term ground, whereas within Europe earth is the norm.

You are using the term to indicate the 0V of the secondary supply – which is not connected to ground/earth; therefore to avoid confusion I would recommend you change the ‘GND’ legend on the PCB to 0V.

You need to ensure that this 0V track is separated from mains by at least 5mm.

Noted!

Thank you, and everyone else here for sharing your knowledge and guiding me in the right direction. I'm really grateful for your time

 

Screw terminals are perfectly acceptable for all electrical connections to the PCB, screwing down onto stranded wire.

We have countless high voltage connections in our machines running through screw terminals like this, but just in the last few years, we were no longer able to pass CE standards with this.

We were told the only way that these high voltage screw terminal connections on stranded wire would meet CE requirements was to use crimp-on ferrules, like in the image below:



I'll admit that I don't know the exact letter of the law, and maybe there should have been other legal ways to get this done, but we were told we had to use ferrules or we couldn't sell into countries following CE standards.

 

ebeowulf17’s images of ferrules provide secondary securement of wire terminations and avoid the 8mm strand issue, but as said, screw terminals acting directly on stranded wire is also acceptable.

If your product is not supplied with a cord for connection to the mains supply, then it is the responsibility of the installer to ensure the connections to the L, N & E terminals is in compliance with local wiring regulations.