Ground is ok? yes I can start

How can I detect that the ground is not connect or connected. The line voltage it's 240Vac or 120Vac and I can have 24Vdc. How can I make a circuit for that.

I really don't know.

 

hi,

are you trying to make a 24vdc power supply with a line voltage of 120 or 220vac primary?

 

You really don't need to make anything...a 24vDC stepdown converter unit should work. You will need to know the current draw of the load though to pick the right power converter.

To check for earth continutity, disconnect the supply and check the resistance between the main earth and the connection in question.

hope that helps