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lboucher
10-25-2009, 07:23 PM
Ok, Simple Simple thing.
Wife has a 25 count strand of regualr minis. with ghosts on each light.
Lights stopped working.

Tried the light keeper pro a dozen times, nothing.
Checked every single bulb and they all work.
Used voltage detector and I have voltage everywhere on the string.
(Even pulled apart the 2 lines at the start a foot apart and both sides have voltage.)
Checked fuses.
Thoughts?

I hate being stumped by small things.

UPDATE:
(Don't remember if i tried light string in different outlet at this point.)
Re-examine fuses and see 1 little wire in fuse block that looked like it might snake around to the other terminal.
Get rid of that wire.
Plug lights into different outlet and they work.
Then back to the bad outlet, and they don't work, go back and forth 3 times and bad outlet never works.
So two different voltage detectors (1 light keeper pro and 1 good one) both detected voltage on bad outlet.
Grab voltmeter and get nothing on bad outlet?
Grab wireing check cube thing (Thing with 3 leds and tests GFCI's)
I think it showed hot and ground reversed (Leds did light. I could be reveresed on colors, didn't watch very long.)
Press test button, leds go out.
5 minutes later i finally found the GFCI.
(The bad outlet is in first floor bathroom, for some reason GFCI is located in master bedrooms bathroom upstairs?)
Probe all outlets on circuit and get nothing.
Reset GFCI and everything is fine. Bad outlet now works.

Any thoughts on what happened?
(Maybe the little wire barely shorted things, somehow kinda half tripping the GFCI resulting in slight hot to ground but not tripping curcit? That just sounds odd?)
Everybody else as thouroughly confused as i am?
Now i am worried about my house wireing or the GFCI in the bathroom.

djulien
10-25-2009, 08:17 PM
Tried the light keeper pro a dozen times, nothing.


By "nothing", do you mean that it shows that a voltage drop is present, or that it shows no voltage drop is there?


Checked every single bulb and they all work.

Did you check them using Light Keeper, or some other steps?


Wife has a 25 count strand of regualr minis

25 count is an unusual number for U.S. Usually it is multiples of 20, 35, or 50. Are those bulbs all in series, or is it some other configuration? (how many wires run between each bulb to the next?)

don

lboucher
10-25-2009, 08:41 PM
By "nothing", do you mean that it shows that a voltage drop is present, or that it shows no voltage drop is there?



Did you check them using Light Keeper, or some other steps?



25 count is an unusual number for U.S. Usually it is multiples of 20, 35, or 50. Are those bulbs all in series, or is it some other configuration? (how many wires run between each bulb to the next?)

don

Sorry

By nothing i meant i pulled the trigger a dozen times, and lights never lit up.
Checked bulbs using light keeper pro.
Maybe its a 20 count strand, didn't count exactly.
See update to my post

LabRat
10-26-2009, 08:45 AM
Sorry

By nothing i meant i pulled the trigger a dozen times, and lights never lit up.
Checked bulbs using light keeper pro.
Maybe its a 20 count strand, didn't count exactly.
See update to my post

Don't know about in PA, but in our local area having the GFCI in one bathroom, with "other" bathrooms downstream is considered perfectly acceptable to code.
So I wouldn't worry too much about the house wiring. I would focus on the GFCI monitoring ... do these actually leak slightly when tripped? The easy test would be to trip another unit (assuming you have one in the kitchen??) and test there.

Photovor
10-30-2009, 08:57 AM
Don't know about in PA, but in our local area having the GFCI in one bathroom, with "other" bathrooms downstream is considered perfectly acceptable to code.
So I wouldn't worry too much about the house wiring. I would focus on the GFCI monitoring ... do these actually leak slightly when tripped? The easy test would be to trip another unit (assuming you have one in the kitchen??) and test there.


In PA, it's ok to have multiple bathrooms running off of a GFCI. The circuit going to that GFCI must be dedicated though. (No lighting circuits or other types of circuits other than downstream outlets)

D_E_H0987
12-11-2009, 04:18 PM
I would bet you have conduit and one of the sections are not screwed together properly, this is real common, I always run a seperate ground wire, as its much better, as if the conduit connectors aren't connected properly, either tightened too little and the thing slips or tightened to much and the screw strips in the zink coupler and the conduit slips, either way ground connection doesn't carry current, best fix is push a seperate ground wire threw the conduit and connect it at each outlet, GFI's only work right if ground connection is good, otherwise they won't save you, so this needs to be fixed, you could also remove the gfi in the bathroom, put in a regular two prong outlet and put a gfi breaker in the fuse box, then the ground would be good to the gfi and it would work right.

I think having seperate gfi's in each area is better though, just a bit of extra protection.

DIY Guy
12-11-2009, 04:50 PM
Also remember GFCIs are not infallible. A GFCI costs $15 at the big box, a gfci breaker is $60. Both are rated for 15A.

Typically when they fail you can't reset them, but you never know.

WireWrap
12-11-2009, 05:22 PM
I would bet you have conduit and one of the sections are not screwed together properly, this is real common, I always run a seperate ground wire, as its much better, as if the conduit connectors aren't connected properly, either tightened too little and the thing slips or tightened to much and the screw strips in the zink coupler and the conduit slips, either way ground connection doesn't carry current, best fix is push a seperate ground wire threw the conduit and connect it at each outlet, GFI's only work right if ground connection is good, otherwise they won't save you, so this needs to be fixed, you could also remove the gfi in the bathroom, put in a regular two prong outlet and put a gfi breaker in the fuse box, then the ground would be good to the gfi and it would work right.

I think having seperate gfi's in each area is better though, just a bit of extra protection.

What you described earlier, (the little wire shorting the hot to neutral) will not cause a GFCI to trip. The GFCI will only trip if the current through the hot lead is not equal to the current in the neutral lead. That is the definition of a ground fault. YOU DO NOT HAVE TO HAVE A GROUND LEAD FOR A GFCI TO WORK PROPERLY!!! Only an imbalance in the hot and neutral currents will cause a trip. If you get across the hot and neutral lines, without a ground path through your body, you will sit there and fry unless you trip the panel's (20 amp or so) breaker. The GFCI will not (and should not) trip.


:)

D_E_H0987
12-13-2009, 12:17 AM
YOU DO NOT HAVE TO HAVE A GROUND LEAD FOR A GFCI TO WORK PROPERLY!!! :)

I don't want to get into a big argument over this.

But how can you tell if something is conducting to ground if you don't have a good ground referance?

I wouldn't want to bet my life on the house wireing, what if its screwed up and the white wire is screwed onto the copper screw rather than the silver one?

Anyway just a couple of thoughts on reasons for a proper ground connection, but if you want to die go ahead, no skin off my back.

WireWrap
12-13-2009, 02:20 AM
...

The GFCI will only trip if the current through the hot lead is not equal to the current in the neutral lead. That is the definition of a ground fault. YOU DO NOT HAVE TO HAVE A GROUND LEAD FOR A GFCI TO WORK PROPERLY!!! Only an imbalance in the hot and neutral currents will cause a trip.

If you get across the hot and neutral lines, without a ground path through your body, you will sit there and fry unless you trip the panel's (20 amp or so) breaker. The GFCI will not (and should not) trip.


:)


I don't want to get into a big argument over this.


That's not the impression you're giving, looking at your last statement.



But how can you tell if something is conducting to ground if you don't have a good ground referance?


That's not how a GFCI works. Try re-reading the explanation I gave in the previous message. If the GFCI detects a difference between the hot circuit and the neutral wire of approximately 5 ma (five-thousandths of one amp) it ASSUMES the possibility of a fault and removes power to hopefully save a life.

Here's a little more information: http://ecmweb.com/mag/electric_gfci_basics/



I wouldn't want to bet my life on the house wireing, what if its screwed up and the white wire is screwed onto the copper screw rather than the silver one?


That's why you should only work with house wiring if you KNOW what you are doing and how to properly test for correct wiring. In the example you suggest, with the neutral tied to the hot outlet screw: I would have to assume that you are also suggesting the the hot (black) lead is connected to the silver contact. If this was a GFCI outlet, this would still trip IN THE EVENT OF A GROUND FAULT in the downstream wiring, as the difference in current between the hot and neutral conductors would open both sides of the circuit.
A GFCI will NOT trip in the event of a short circuit, where the current is only flowing in the hot and neutral conductors. As long as it remains equal, the GFCI is not tripped.



Anyway just a couple of thoughts on reasons for a proper ground connection, but if you want to die go ahead, no skin off my back.

And no brain in your head, either. Still waiting to see evidence of the few thoughts... There are many reasons for proper grounding, but they are delineated in the National Electrical Code, not your imagination.



:) Note my signature: :idea: :idea: :idea:

lboucher
12-14-2009, 06:17 PM
Sorry to have gotten everyone riled up.

In the meantime, ever since i reset the GFCI the circuit has worked fine.
I assure all that read this, i truely did understand GFCI's at the start and yet was throughouly confused by the symptoms of the problem. Wish someone else had been around to ensure me i am not crazy.

Lucas

WireWrap
12-14-2009, 09:12 PM
Sorry to have gotten everyone riled up.

In the meantime, ever since i reset the GFCI the circuit has worked fine.
I assure all that read this, i truely did understand GFCI's at the start and yet was throughouly confused by the symptoms of the problem. Wish someone else had been around to ensure me i am not crazy.

Lucas

I didn't mean to imply that you didn't, Lucas. I just wanted to correct D_E_H0987's erroneous statement that a GFCI needs a good ground connection or it won't work. Obviously, (s)he needs to do a little more studying.

However, you won't find anyone willing to vouch for your sanity. You're involved with leetle flashy lights at the expense of your whole year's spare time, aren't you???


:)

JonathonReinhart
12-14-2009, 10:05 PM
I completely agree with WireWrap here. This is one of the common misconceptions that I cannot seem to get people to understand. A GFCI does Not do anything with the ground conductor, and it is not required for the device to provide ground-fault protection. Don't believe me? Read up on how they work (http://en.wikipedia.org/wiki/GFCI).

It works simply off the difference between the current leaving the hot conductor, and returning in the neutral. This is why you can safely (and is recommended to) use a GFCI when replacing a two-prong outlet that has no ground conductor. I think I saw this in the NEC somewhere?

We all need to be careful when posting information to others, to be certain that we do not lead them astray. If you aren't certain of something, do not post it.