2 supplies

[flameport]

we have a communal unit that is wired from 2 seperate supplies

This drivel has been suggested before, //www.diynot.com/diy/threads/advice-sought.466944/
and the answers now are the same as they were then.

Not permitted, dangerous and totally unacceptable.
If you install such a thing, the DNO will disconnect both supplies without notice when they find out.

 

[Echo the husky]

I thought it had! I got confused when the replies looked exactly like the old replies!