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Power at Ceiling fan reading 30 volts instead of 120 volts

Power at Ceiling fan reading 30 volts instead of 120 volts

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  #1  
Old 06-27-15, 03:58 PM
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Power at Ceiling fan reading 30 volts instead of 120 volts

Hello,
My ceiling fan and light have been installed for a couple years and the fan and light both stopped working recently. It uses a wireless remote so the original wall switch was removed and wired together. When I pull down the fan and measured the voltage coming out of the ceiling its showing only 30 volts. I pulled the cover plate off the wall where the old switch used to be and checked the voltage here and its showing 120 volts. I have checked Hot to Neutral and Hot to Ground. Same 30 volts at both. Any ideas?
I read on another forum that someone had similar issues and it was a loose wire on one of the other outlets in the room. I pulled all the outlets out and verified the wires were tight.

Thanks in advance for any help.
 
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Old 06-27-15, 04:33 PM
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Do you have two 2-conductor cables (black, white) at the switch? Do you have only one 2-comductor cable at the fan?
voltage coming out of the ceiling its showing only 30 volts.
Was this a digital multimeter? If so you are probably seeing phantom voltage.
 
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Old 06-27-15, 04:39 PM
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There are black and white wires at the fan. I am using a digital multimeter.
Can you explain the phantom voltage?
 
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Old 06-27-15, 04:47 PM
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There are black and white wires at the fan.
Not an answer to my question.
Do you have two 2-conductor cables (black, white) at the switch? Do you have only one 2-comductor cable at the fan?
In other words do you have two white wires and two black wires at the switch and only on black and one white wire at the light?

Phantom voltage is a false reading due to induced voltage. It is why we recommend an analog multimeter. http://www.doityourself.com/forum/el...m-voltage.html
 
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Old 06-27-15, 04:51 PM
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Sorry, at the switch there are two white and two black wires. At the fan there is 1 white and 1 black wire.
 
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Old 06-27-15, 05:05 PM
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at the switch there are two white and two black wires.
That is two cables. One cable (disconnected) when measured across the black and white should be ~120v.
  • Separately cap the black and white of that cable.
  • Verify that the other cable reads 0 between black and white. That is the cable to the fan.
  • With breaker off connect the black and white of the cable to the fan together.
  • Disconnect the cable at the fan.
  • Set the multimeter to ohms and check for continuity between the black and white of the cable. You should get continuity.
 
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Old 06-27-15, 05:27 PM
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I separated the wires at the switch. 1 black and white pair is showing 120 volts as expected.
The other pair though is showing between .8 and 1 volt. Why would the second pair show 1 volt?
Can I still tie this second set (1 volt) together and check for continuity?
 
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Old 06-27-15, 06:29 PM
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The other pair though is showing between .8 and 1 volt. Why would the second pair show 1 volt?
It's really ) but you are using a digital multimeter so false voltages are common. Ignore the reading and connect them together.
 
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Old 06-27-15, 07:07 PM
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At the switch box, I connected the white and ground together and checked for continuity at the fan. My meter generates a tone as expected.
I disconnected those and connected the white and the ground at the switch box. When I check for continuity at the fan, I do not get a tone this time. I disconnected and reconnected at the switch box but could not get it to show continuity.
 
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Old 06-27-15, 07:14 PM
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At the switch box, I connected the white and ground together and checked for continuity at the fan. My meter generates a tone as expected.
I disconnected those and connected the white and the ground at the switch box. When I check for continuity at the fan, I do not get a tone this time.
But what about black and white I asked you to test?
 
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Old 06-27-15, 07:36 PM
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Sorry, at the switch box, I connected the black and white going to the fan together. Then I checked for continuity at the fan. No tone from the meter. I have to assume something has happened to the black wire from the switch box to the fan. Not sure how this can happen after 10 years.
 
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Old 06-27-15, 07:52 PM
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I have to assume something has happened to the black wire from the switch box to the fan. Not sure how this can happen after 10 years.
Yes. How hard to run a new cable? Is there an unfinished attic above?
 
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Old 06-27-15, 08:05 PM
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Unfortunately, no unfinished attic above. Its a bathroom above and no easy way to run a new wire.
 
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Old 06-27-15, 09:40 PM
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Have you recently hammed any nails or driven any screws near the switch box or did any work in the bathroom above?
 
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Old 06-28-15, 03:24 AM
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Just one more thing you can check as a thought of mine. You say this fan has been working for years now. Maybe a loose wire (nut not tight enough thus causing no power to conductor).

I have to assume something has happened to the black wire from the switch box to the fan. Not sure how this can happen after 10 years.

The fan ceiling box: When you removed the fan have you looked up into the box to see if there are any wire nuts that connect to the wires coming to the fan? Or are you just working with the wires coming directly to the fan. It is quite possible that someone when installing the fan used jumpers from the conductors going to the ceiling fan box to the fan itself because maybe the original wires going to the fan box were not long enough. Look deep inside of fan box with breaker off. See how many wires (conductors) are back there. It is possible that if jumpers were used and the wire nuts were not tight enough or the person installing the wire nuts did not twist the conductors together and just put the wire nuts on that over time with the vibration of the fan etc the nut has come loose thus the conductor is not making full contact.
 

Last edited by AFJES; 06-28-15 at 03:54 AM.
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Old 06-28-15, 06:10 AM
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Have not hammered or screwed anything into the walls or ceilings.

I will check all the wires in/above the box today.
 
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Old 06-28-15, 09:28 AM
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Afjes' reply should not apply to your situation. Why did you answer as if it does?
I will check all the wires in/above the box today
There should only be two wires and they should be disconnected already in the ceiling box. There should be no other wires to check and there should be no wire nuts.
 
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Old 06-28-15, 11:01 AM
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Ray, I am just trying to check everything I can. I have done basic wiring, but I am no expert.

It became more complicated this morning. I pulled all the wires out of the switch box all the way to find that the cable going to the fan is a 3 wire with the red capped off. I then pulled the box out of the ceiling and its only a 2 wire. I have pictures of when the house was being built, but all I can see in the pictures is the two cables in the switch box (1 two wire, 1 three wire) both go down into the basement (no idea why). I traced the 3 wire across the basement ceiling where it then goes back up one of the outside walls.
Net is at some point it goes from 3 wire to 2 wire and there are no exposed junction boxes. I am stumped.
 
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Old 06-28-15, 12:07 PM
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Ok folks, stupid me figured it out. On the other side of the room there is another switch and that's there the 3 wire cable was running. Someone turned this switch off. To be honest I don't recall it controlling this fixture.

While checking this switch box I found two more potential issues:
1) This one is definitely a problem. There are three switches in the box. When I pulled them out to check the wires, I see a spark back in the back of the box. Turned off the power and found the white wire was cut through 90% of the way and as soon as I grabbed it, the wire broke into two pieces. So if nothing else, this whole adventure may have saved me a fire in the future.
2) In this switch box, there are three different circuits running. One to the fan, One to a light in the room next to it and one to a light at the top of the stairs in front of the switch box. I noticed that the electrician tied all the ground wires together. Can you have the ground wires for different circuits connected together?

Thanks for all your support on the first issue and sorry to waste your time.
 
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Old 06-28-15, 12:23 PM
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Can you have the ground wires for different circuits connected together?
It's required by code. .
 
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Old 06-28-15, 12:26 PM
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Thanks Ray and everyone else
 
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Old 06-29-15, 03:19 AM
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You did not waste our time and glad you found the issue with the broken wire. Apparently your three way switches are not set up properly if the first switch had the red wire capped off. The switch on the opposite wall if the switches were set up properly should not have prevented you from turning the light on from the first switch.
 
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Old 06-29-15, 10:32 AM
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The switch on the opposite wall if the switches were set up properly should not have prevented you from turning the light on from the first switch.
The switches are not suppose to work. They were bypassed so the fan was controlled by a remote.
You did not waste our time
I agree but multiple times he didn't follow instructions. He was asked how many cables in the switch box but he didn't seem to have really looked. I'm not even sure he pulled the fan to run the continuity test. I'm okay with that. Heck, I misread posts all the time then screw up replying.
 
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