Hi, and happy new year by the way !
I am new here and electricity is not my domain ! I am however very careful when playing with it ( turning power off always :-) and always worried about having it done the right and safe way.
here is my problem.
Located in the USA.
I wanted to installed a roof and gutter deicing cable. I have a double outlet?socket http://www.istockphoto.com/file_thumbview_approve/2858502/2/istockphoto_2858502_electric_socket.jpg outside that I was planning to use. The instructions for the cable requires a grounded outlet. I have checked both with a simple neon tester http://img.alibaba.com/photo/10869773/4_Way_Circuit_Tester.summ.jpg

1 needle in small hole, 1 needle in big hole = light
1 needle in small hole, 1 needle in ground hole = no light
1 needle in big hole, 1 needle in groud hole = no light

The wires (one white, one blue) are coming from inside the house in a metallic tube to connect with the outlet outside, located against the wall in a plastic box.

What do I have to do to ground this outlet so I can use it for the deicing cable?

Thanks a lot

The instructions should also state that GFI Protection for Equipment is required. This is not your standard GFI circuit breaker or receptacle.

This requires 30 MA (Milliamp) protection, not the 5 MA from a standard GFI device.

This can only be provided by a 30 MA GFI breaker made for your particular panelboard, and these are not cheap. Or some deicing products offer GFI protection in their deicing controller or thermostat.

As far as grounding the outlet, you mention tubing. If this is a metal conduit system, the conduit may be grounded, and can be used as an equipment grounding conductor. You would need to change the plastic box to metal, and connect the ground wire from the outlet to the box. Note, this is ONLY if the conduit is a grounded complete system.

Or, better, would be pulling through the conduit a new equipment grounding conductor.

Other than these two solutions, there is no other method you can use to ground the outlet.

Thanks

The instructions should also state that GFI Protection for Equipment is required. This is not your standard GFI circuit breaker or receptacle.

This requires 30 MA (Milliamp) protection, not the 5 MA from a standard GFI device.

This can only be provided by a 30 MA GFI breaker made for your particular panelboard, and these are not cheap. Or some deicing products offer GFI protection in their deicing controller or thermostat.

As far as grounding the outlet, you mention tubing. If this is a metal conduit system, the conduit may be grounded, and can be used as an equipment grounding conductor. You would need to change the plastic box to metal, and connect the ground wire from the outlet to the box. Note, this is ONLY if the conduit is a grounded complete system.

Or, better, would be pulling thru the conduit a new equipment grounding conductor.

Other than these two solutions, there is no other method you can use to ground the outlet.

Requirements are 20 MA and GFIProtection. How can I find out if that is what I have on the main electrical box where all the circuit breakers are?

For now, I won t use the deicing cable. I have screwed a metal box to the metal conduit and installed a self grouding outlet. When I do the check for ground as mention in my first post, the tester now lits up. I have ground, Is that correct that the ground is now made through the outlet>>box>>metal conduit ?

Do I also need to connect the green screw on the outlet to the metallic box? Another screw and location for that are available. If yes, I would need a very short wire, what diameter?

How can I be 100% sure that the conduit is indeed a grounded complete system.

I am sorry I don t know the electrical terminology at all and I probably embarrass myself here, but better safe than sorry. Thanks for anykind of help.