Hi,
I am working on a rental property of mine and I was changing out the ceiling fans. Before I installed the new ones I checked with a meter to see if the power was on at the ceiling location. I found it was so I flicked the switch at the door, checked it again, still hot. Checked all the outlets in the room to see if the switch controled any of these. It did not. I thought the switch may be faulty. It checked out fine. I then discovered that both wires to the switch were hot. I completely disconnected them from the switch and tested them again, hot. Should I remove this circuit and just run a new circuit for these fans (2)?
Thanks,
Mike
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It may not actually have been hot. If you used a meter that doesn't
present much of a load, it may have shown a coupled, "stray" voltage.
Put a light or something across the wires to see if it lights.
Also, the switch may be for something like an outside light...
Be careful, and good luck! Let us know, will you?
Brooks
Thank you,
I'm sorry I should have said i used a "no touch" voltage detector, does that make a difference? Lights up and beeps. When the switch is removed both cables indicating hot as per tester. I'll have more time tomorrow to check it out. I'll let you'all know how it goes.
Mike
Yes, the tick tester will often give false positives.But that does not mean tht it is a false postive in THIS CASE.
I have one of those I bought for checking Christmas tree lights. Thing beeps when I move it near my hand. I know I have an electrifying personality, but not that much. :)
Use a volt meter or light, and be careful. Even the cheapy Harbor Freight voltmeters ($3) will work well enough for this.Pete Duffy, Handyman
One of the two wires at the switch should be hot; that's your line. The other--your load--shouldn't be...unless the switch is on. If both are hot, and it's not stray voltage as mentioned above, something's wrong and you need to trace the circuit and find out what it is.
If that switch is a three-way, however, things are different. How many terminals are there on the switch body?
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Only 2 terminals. I'll get up in the attic tomorrow and follow it back to see where it comes from.
Mike
Hint: If you don't have an assistant to stand by and throw switches or circuit breakers on and off as you need them thrown, use a portable radio as your current tester. You can hear it go on or off as you modify the condition of the circuit you're working on. Real useful when you can't be in the same room to see a test light.Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Yes, this situation keeps running over in my mind, if you have two hot wires connected by a switch shouldn't something "happen", breaker tripping or the like??
mike
If they are independent hots feeding together from opposite sides of the switch, yes, something should blow as soon as the switch is closed (turned on).
It is likely your proximity voltage tester wasn't adjusted to a low enough sensitivity when you tested those two wires. If you set the sensing pot too high, it can read voltage from 2 or 3 feet away. When I use mine, I stick the probe into a known hot outlet, then crank the pot down till it does not indicate voltage even with it's hard-up against it. Then I turn it up verrrrrry gradually until it just starts to beep and flash. Set like that, I can stick the probe into the neutral slot on the same outlet and get no reading.
Those gizmos are useful when you have to trace hot lines behind walls or ceilins; and if you're used to them, they can save you some time figuring out just what that mess of 9 wires crammed into one 4" octo box really is. But a good old-fashioned $2 pigtailed neon test lamp is still the tool of choice when you want to know where the juice is.Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Thank you,
Yes, I do have a feeling it's me just reading it wrong. I'll try with the neon tester tomorrow and I'll let you know. Now I think on I have only used the no touch voltage detector on the actual sheathed cable and not individual conductors, so it would make sense of what some of the other posts have pointed out about it picking up stray voltage. I guess I just didn't understand how that gizmo actually worked.
Thanks again,
Mike
Edited 8/30/2006 10:15 pm ET by MBaybut
Remember: there are two ways that a simple SPST switch can be wired.
1. For a switch leg--this is where the power comes directly into the fixture box (in the ceiling, usually) but the hot wire is sent back out to the switch box whereever that is, cut and wired across the switch (one end on each terminal), and sent back to the fixture box again...all before being connected to the fixture itself. Thus, when the switch is opened, the hot wire on the load side of the fixture box goes dead;
or
2. As an in-line interrupter--This is where the power feed passes through the switch box itself first, but the hot lead is cut there and the switch inserted between the two cut ends. From the switch box, the power feed continues on to the fixture box, whereever it is, but the hot is only live when the switch is closed. (In this configuration, there is no unswitched hot power available in the fixture box as there is in configuration #1.)Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Thanks,
As pointed out by my friends here, I was getting a false positive. Went ahead and used the neon and a meter both confirm switch was working correctly and circuit was good.
Thank you so much.
Mike