Electrical issue with AC consumer unit

[ianj99]

What is the purpose of the earth connection ?

For testing it by providing a path for the 10ma trip current. My EV charger 10ma Schneider RCDO has a test button next to the lever.

 

[PaulRainbow]

RCBO's also often have an earth wire, or at least the type I have for my EV charger does. L in and out, N out , blue wire for the N in and g/y earth. (it's single width version)
The earth is for testing it and there is a small button next to the lever. If there isn't a test button, its probably a dp mcb with Live + switched Neutral.

RCBOs without Earth wires still have a test button.

 

[ianj99]

RCBOs without Earth wires still have a test button.

yes.

 

[starfire]

yes.

They put a test resistor across L & N but one end on the supply L & the other on the load N.
That unbalances the rcd sensing.

Some still use an earth connection to provide the test connection

 

[rogerthebodger]

Looking at the diagram I posted it looks like its only connected to the current difference from the line / neutral and driving the disconnect relay.

As Paul says there are coming out without the earth so some one has designed a system that does not require a PE connection

I note its called FE what ever that means.

 

[starfire]

Looking at the diagram I posted it looks like its only connected to the current difference from the line / neutral and driving the disconnect relay.

As Paul says there are coming out without the earth so some one has designed a system that does not require a PE connection

I note its called FE what ever that means.

Functional earth