what does "open ground" mean?

tomseeley · 11-11-2009, 02:25 PM

I've got two ceiling lights in my upstairs hall, both controlled by two wall switches. One light doesn't work but it's not a bad bulb. I suspect it's on a circuit that isn't working, either, but I'm not sure.

I plugged in one of those little circuit tester gizmos, that shows various patterns of yellow, red, or no lights, indicating various conditions. I plugged it into a 3-prong socket I THINK is part of the same circuit the bad ceiling light is on, and the gizmo says "open ground".

What is it telling me? What should I expect to find, if I take the plate cover off and examine the guts of the wall socket?

I'm a pump/pipe/valve guy, not a wiring guy, so keep it simple if you answer me, please

I think a switch is something that pinches the wire and stops the electrons from moving through it!

300zx · 11-11-2009, 02:33 PM

Quote:

Originally Posted by tomseeley

I've got two ceiling lights in my upstairs hall, both controlled by two wall switches. One light doesn't work but it's not a bad bulb. I suspect it's on a circuit that isn't working, either, but I'm not sure.

I plugged in one of those little circuit tester gizmos, that shows various patterns of yellow, red, or no lights, indicating various conditions. I plugged it into a 3-prong socket I THINK is part of the same circuit the bad ceiling light is on, and the gizmo says "open ground".

What is it telling me? What should I expect to find, if I take the plate cover off and examine the guts of the wall socket?

I'm a pump/pipe/valve guy, not a wiring guy, so keep it simple if you answer me, please

I think a switch is something that pinches the wire and stops the electrons from moving through it!

Open ground means you have no ground .If you have grounds in your rec then you need to trace down where you lost it, as far as the light goes the light that is working take down and check the connections if they are good there then take down the one that is not working and check it grounds should not make the light not work but you need to fix that problem for safty.Turn OFF POWER WHEN WORKING WITH THIS PROJECT.

darren · 11-11-2009, 05:26 PM

Quote:

Originally Posted by tomseeley

I think a switch is something that pinches the wire and stops the electrons from moving through it!

Thats exactly what a switch does, that is why over time the switch gets easier to use the wire is more squished and less effort is required to pinch it.

Now a dimmer has a variable pincher in it, the more you let off it pinches a little less and lets a few more electrons through and makes the light brighter.

Billy_Bob · 11-12-2009, 09:57 AM

The ground on an outlet is the third round hole for the plug. Your tester is indicating that this connection is not connected to the outlet or that the wire connected to this is broken/not connected upstream from that outlet.

The ground connection is an important safety feature of electrical systems. This could be an indication of some very serious problems. Or it might be you have an older house without "grounded outlets"/wiring and someone replaced a 2 prong outlet with a 3 prong outlet.

In either case, you should have an electrician take a look at your electrical system. If a "main ground" connection has come loose or was removed/broken, this would be a SERIOUS problem!

Also sometimes the main electrical system ground is connected to a water pipe, then the metal water pipe is replaced with plastic pipe. This can cause this problem. Again electrician thing...