Mini Trees and GFI's

[Wayne K]

Got up this mourning to find several of my gfi plugs tripped after we had rain here last night. After a lot of unplugging and plugging back in, My biggest problem seams to be with my mini tree's since they have a direct ground path to earth by being pushed into the ground and I can see that some of the socket end's are right next to the metal rods of the cage. Has anyone come up with a good fix for this ? I am wondering about getting some automotive vacuum tubing and sliding over the cage sides where you wrap the lights around them so there is a rubber barrier between the lights and the cage and then wrapping my lights around them. Has anyone tried this ? How good are the new led lights sealed up where the wire comes out ? Are the new led lights more or less susceptible to this kind of problem since I think they are rectified to dc

Thanks

Wayne

[Guest guest]

I wrapped mine in vinyl chicken wire (home depot) first, and have not had any problems. My plugs inside the tree hang in the middle, so not touching the metal frame. It's a pain wrapping them with the vinyl, and no way to definitively say that has prevented any GFI trips, but I am trip-less this first year.

I also have my plugs connecting me back to my controller boxes elevated off the ground, unwrapped, of course.

[Dennis Cherry]

It does not make difference if the lights are incandescent or LED's.

It is the number of times the light string wires are touching the wire frame.

Things to consider:

Insulate the wire frame by using a vinyl paint on the frames.

Loosely wrap the wires on the frame and if using zip ties do not over tighten them, this will put a strain on the insulation.

Try to insulated the frame from ground, by using wood dowel, PVC, something.

Keep the all plugs off the ground and inside the mini tree suspended.

Do not wrap black tape on the plugs to keep them water tight, it does the opposite, it keeps water in the plugs. If that was needed, then UL would have put that notice on the light string labels.

Use some other non conductive materials for the mini trees such as Coro.

Just some things.

BTW: last year used wire frames and had many GFCI trips when it rained, this year used Coro and not one trip from anything in my display.

[wallleyes]

I went to the dollar store and bought some black plastic pails that my 32 inch tomato cage mini trees fit over the edge of the pail.I then just used some self taping screws to hold them together.It also raised my mini trees up a foot which helped keep them from getting buried in the 2 feet of snow that blanketed my display.

[DanCampbell]

I resolved the rainy night in Georgia GFCI trips on the minitrees last year by cutting some scrap vinyl flooring into mats to get the bottom ring off the ground. Cut a smaller hole in the center for a tent stake to use for tying it down.

The leakage through a couple of trees wasn't enough to cause the trip, but when all 8 were lit it hit the threshold.

I don't remember where I found that suggestion, but it worked like a charm.

[JeffF]

I just use 2"x2" furring strips under our 16 mini-trees. And once the snow gets to 2" you can't even see them, but they still do the trick.

-Jeff

[friskybri]

I used 1/4 inch plywood painted black about 2 inches wider then the mini tree. Then I took 3/4 inch pcv couplers and glued on the 4 corners to raise it off the ground about 2 inches. Had to do this after I wrapped the mini trees and they started to pop the GFI's. Now in a heavy rain I have no problems.

[-klb-]

I do think the open bases of the incandescent sockets do add some leakage over sealed LED strings. We have far fewer trips of the city park lawn fan this year, than last. We have doubled the size/number of strings, and have more stuff on one GFCI, and still far fewer trips.

But, Dennis is right, there is also a capacitive coupling issue that can happen even with sealed bases.

The mini trees I use at home and at the park have 3 1/4-20 nuts welded to the base. Then I have 1/4-20 anchor bolts with the wood thread anchor screwed into plastic tent stakes. This lets me elevate the frames a bit, and completely isolate them from ground. It tends to be very reliable.

[Wayne K]

Thanks for the reply's, But doesn't isolating the base from the ground make these metal cages electricaly hot in a sense if there is a small amount of electrical leakage from the lights? Since these plugs are not polarized I know last year I went out and turned the plug 180 degrees on the trees I know I had trouble with and stopped the gfi's from tripping. So in my mind you are relying on those gfi's to now trip when you or someone or thing touch the cages ( I know that is what they are suppose to do, but what if it doesn't work ) A cage is a lot bigger object for someone to contact rather than a cord or plug or something like that. Maybe my thinking is off, but these were my first thoughts about isolating the cages.

Wayne

[-klb-]

1) Get a test plug, and test your GFCI regularly.
2) my mini trees are far enough from the edges of the yard, or garland fence in the park that people should not be reaching to it
3) If they do reach out and touch it, they are so densely wrapped that they will likely touch a glass bulb, or insulated string first. Touching the frame would take some work.
4) Many of the issues with mini trees tripping are cases where no single tree causes it to trip, so no single tree has a large enough leak to be fatal.
5) Most visitors have well insulated shoes on, so they are unlikely to get zapped anyway.

Yes, there is still some risk, but it is going to take multiple failures. At the same time, you try to minimize the number of known failures at any one time. (thus testing GFCI every season)

As for why turning 180 degrees may help, not only are the plugs not polarized, but the mini lights don't have any safety preference for one orientation than another. If you have one that trips plugged in one way, and not the other, that says to me that your leak was closer to the end originally plugged into hot, and you are now feeding that end of the string neutral instead, so that there is now a lower voltage between there and ground, and less current flows.

For C7 & C9, the screw thread of the base is supposed to be neutral, as it is most likely to become exposed. The tip, which is most protected in the socket, and breaks contact fastest when unscrewed is supposed to be hot..

On mini lights, each side of each socket is only 2.5 volts apart.. For each half string of a 100 mini light set, you have 3 wires. You have a hot and neutral that run to the second half and/or to the socket at the end. That third wire is your string of 50 sockets in series, and connects to hot on one end, and neutral on the other.. Which end is which depends on which way the non polarized plug is inserted. Or in other words, plugged in one way, the 10th socket will be about 25 volts from ground when running. When plugged in the other way, that 10th socket will be more like 85V from ground, and the 40th socket will be the one that is 25V from ground.