Help with powerless light fixture..

[farseer]

Hi,

I have a big problem i hope someone may be able to help with. This is a bit complicated, so please bear with me while i explain the layout...

I have a three-way switch that controls three lights (one light is located downstairs by the entrance, and the other two are just up the stairs from there...the 2nd floor hallway). The first switch is upstairs and the second is downstairs. The down stairs switch is located next to two other switches, each on a different circuit breaker.

Everything was working fine...until i attempted to install some dimmers. I had accidentally used the source from a different circuit for the second three way switch (i connected it to the common of the

2nd switch). Need-less-to-say, when i turned the breaker back on...BOOM! The main breaker tripped. Ok, so i got a new swtich and this time correctly installed it (travels to the 2nd switch and common to light fixture wire). I CONFIRMED that 120V is leaving the 2nd switch heading towards the downstairs light fixture. The problem is, now none of the lights work. No current seem to be flowing to the light bulb. Any ideas what happened here?

-Since i know 120v is being sent from the 2nd switch (via the common), How can i check continuity between the 2nd switch and the light fixture?

-Is there a way to send a signal of any kind from the switch node to the fixture and test if it gets there?

-Also, what is the proper way measure the voltage of light fixture. this light fixture has a bx cable with whith and black wire. The way i have been testing using my multi-tester is touching the red probe to the black wire, and using the fixture itself as the ground. Is that correct?

Thanks for any help you can offer (i am clearly not an electrician...so please explain in layman's term).

[terry]

Item, (1)

Suggestion; You clearly understand the idea of the first switch 'sending' the voltage to the second switch. Suggest that as a next step you make sure it is 'arriving' at the second switch. Depending in which position is the first switch the voltage will be on one or the other wires to the second switch. OK so far?

Then depending on the position of the second switch the voltage will or will not be sent to the light fixture/s. Once you know it's arrived at the second switch you can figure why/how it's getting, or not getting to the fixture. Yes there is a way; just rig up a temporary connection to some source of AC voltage from either a live wire within that switch box or from an extension cord. that should 'prove' the wiring to light fixture.

Item (2)

Suggestion: Good enough, assuming all grounds are OK. You are only looking for voltage. But many test meters are far too sensitive and can sometimes give false/misleading readings. Its often better to use a bulb, either in a holder with a couple of short leads or even just touching one side of the bulb base to ground or neutral and the other to the wire you are testing to see if it is alive. I used a bulb that way tonight to make sure voltage was arriving a new switch for some workshop ceiling lights (just touched the base of the bulb temporarily borrowed from nearby cos i was too lazy to go upstairs and get a spare), to the wires. It was; the bulb lit. Clearing up later couldn't figure why the stair light didn't work. I had borrowed that bulb for testing cos it was easy to reach!

[maradcliff]

Shut off the power, take a digital or analog test meter and get enough extra wire to run across the room to the other switch. Set the meter on OHMS. Put one test lead on the wire by the switch where you are standing, put the other test lead to the spare wire, and hook that wire to the switch on the other wall.

[farseer]

Since 120 is leaving the second switch, it has to be arriving at that switch (assuming it's from the travellers from the first switch). I went a head and verified that it is indeed arriving from the travellers. i was able to do this by toggling the first switch on and off. when i did this, power alternated between one of those two travellers, connected to the second switch, which it should.

this then leaves the connection from second switch to the fixtures. there are three fixtures in series. i don't know which is first. is it possible that wone of those has a loose connection that was jarred apart by when the circuit tripped? So you are thinking this is likely a fixture issure and not the wire itself, correct?

I will try testing the bulb itself like you said. From what i understand, you are saying i can connect a bulb DIRECTLY to a 120v feed wire?

thanks fo ryou help.

idea of the first switch

[farseer]

I am interested in trying this. but i'm not clear as to what you are instructing what you are instructing.. Given this diagram:

Where should i hook up the extra wire too and where should the leads of my Multi-meter touch?

thanks much >Shut off the power, take a digital or analog test meter and get enough