Electronic – How to check if something is mains earth grounded


Suppose I would like to verify that the ground terminal on an indoor power outlet is actually connected to the ground (from what I've read, some of them aren't!). How would I go about checking that?

I ask because I recently purchased an ESD wrist strap, but I know it's useless unless it's actually connected to the earth.

Best Answer

You can use the continuity function on your multimeter for this, connect one end to the ground of the power outlet and the other to any other point that you know to be grounded. Not sure if there are any safety issues involved but I've done similar with my bench power supply and scope and it worked well.