Grounding the project enclosure

My project uses 12V DV powered my a walwart. Do I need to ground the enclosure?

Thanks in advance for any help.

No there is no need to ground the enclosure. The wall wart is double insulated.

If your power is coming in as DC from a wallwart there is no earth wire to ground it to in the first place.

The above comments apply to safety. If you want good EMI shielding, it helps to ground the case. For example, with audio circuits.

Thanks, guys.

aarg:
The above comments apply to safety.

Good to know. That was my main concern.

If you want good EMI shielding, it helps to ground the case. For example, with audio circuits.

MarkT:
If your power is coming in as DC from a wallwart there is no earth wire to ground it to in the first place.

So how would you ground the enclosure in this case?

Connect it to a mains ground pin. This will mean another socket, or get a power supply that uses the ground pin.

I see. Thanks.

And mains ground should NOT connect to 0V, right?

Feddar:
I see. Thanks.

And mains ground should NOT connect to 0V, right?

It depends on whether or where you want your circuit to be grounded. Sometimes it is forced on you by connectors that have a conductive housing that contacts the chassis, like phone plugs. It's usually harmless, sometimes necessary.

If you have a system where multiple chassis are interconnected with cables, sometimes grounding all of them can create "ground loops". In that case, you want only one device to be grounded, and all the others to get their ground from the cables.

Feddar:
I see. Thanks.

And mains ground should NOT connect to 0V, right?

It can be and often it should be it depends. Any power supply has some small leakage current which can upset analogue readings. However in a situation where you have many power supplies connecting zero volts to ground will trip the residual current trips in many mains systems.

As a rule don't do it, keep it in reserve for when you need to do it.

Thank you very much, guys. Much appreciated.