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First-light
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I'm installing dimmer switches (Lutron CL) for overhead lighting. I installed three the same exact way. 2 when shut off leaves a load on the hot wire to the fixture.

My voltage tester reads a load. The one dimmer switch when off has no load. I'm scratching my head on this. Went online to get some info and I hear you can have a phantom charge leaking out of a dimmer switch. I went back and put new regular switches in and it works fine no load when shut off. Any thought on this would be great! 

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1 hour ago, First-light said:

I'm installing dimmer switches (Lutron CL) for overhead lighting. I installed three the same exact way. 2 when shut off leaves a load on the hot wire to the fixture.

My voltage tester reads a load. The one dimmer switch when off has no load. I'm scratching my head on this. Went online to get some info and I hear you can have a phantom charge leaking out of a dimmer switch. I went back and put new regular switches in and it works fine no load when shut off. Any thought on this would be great! 

When you say  they leave a load  do you mean you are reading voltage on he load side of the dimmer to ground  ?  If so how much voltage.   What made you check voltage ? do the lights stay on dim when the switch is off ?

 

Edited by mjac
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2 hours ago, mjac said:

When you say  they leave a load  do you mean you are reading voltage on he load side of the dimmer to ground  ?  If so how much voltage.   What made you check voltage ? do the lights stay on dim when the switch is off ?

 

When dimmer switch is off there is a load on the black (hot) wire. No the lights are not on. Don't know what voltage is reading I have to borrow one that reads voltage. I was going to cut the wire to add another sconce so I shut the switch off just by habit I checked the hot wire and there was a load. 

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28 minutes ago, First-light said:

When dimmer switch is off there is a load on the black (hot) wire. No the lights are not on. Don't know what voltage is reading I have to borrow one that reads voltage. I was going to cut the wire to add another sconce so I shut the switch off just by habit I checked the hot wire and there was a load. 

With the switch off,  one black wire at the switch ( coming from the source ) will always  have power on it   you need to shut off the circuit breaker  feeding that black (hot) wire. .   The other black wire   ( going to the light ) will not have power .   

 With the switch on, both black will have power.

I am assuming that when you say a load on it  you mean power. 

 A load actually means the component that the power is feeding  ie; light, motor , pump etc..

Phantom power is sometimes picked up by certain testers when there is an energized wire in the same harness or box.  This voltage has no power behind it and is usually low volts maybe 40-50 volts, it will disappear as soon as a load is put on it.  You might be seeing that phantom power if the switch is off and both black wires have voltage on them  one 120v and one 50volts . Usually those lighted testers pick up phantom,  a voltmeter most cases do not.  Either way  always shut off the circuit breaker when cutting wires. 

 

 

Edited by mjac
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21 minutes ago, mjac said:

With the switch off,  one black wire at the switch ( coming from the source ) will always  have power on it   you need to shut off the circuit breaker  feeding that black (hot) wire. .   The other black wire   ( going to the light ) will not have power .   

 With the switch on, both black will have power.

I am assuming that when you say a load on it  you mean power. 

 

 A load actually means the component that the power is feeding  ie; light, motor , pump etc..

Sorry about load and power. Switch on there is power on the black wire to lights, lights work fine. Switch off still read power on black line to lights, lights are off. 

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20 minutes ago, First-light said:

Sorry about load and power. Switch on there is power on the black wire to lights, lights work fine. Switch off still read power on black line to lights, lights are off. 

I have a feeling its the tester picking up stray voltage "phantom" since the lights stay out with the switch off.  

Phantom power is sometimes picked up by certain testers when there is an energized wire in the same harness or box.  This voltage has no power behind it and is usually low volts maybe 40- 100 volts, it will disappear as soon as a load is put on it.  You might be seeing that phantom power if the switch is off and both black wires have voltage on them  one 120v and one lower volts . Usually those lighted testers pick up phantom,  a voltmeter most cases do not.  Either way  always shut off the circuit breaker when cutting wires !  

 

 

 

Edited by mjac
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First light, if you are using a non contact voltage tester (the type that lights up or has an audible signal to indicate presence of voltage) then, yes, they will detect a small amount of induced voltage on the switch leg due to its proximity to the feed which is always "hot".

Also, those types of testers are not the most reliable. They are called "widow makers" for a reason. Trash that thing and invest in either a solenoid type tester, or an inexpensive multimeter.

Sent from my SAMSUNG-SM-G930A using Tapatalk

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He has been busy working  and not on forum much but I did text him the link 


I talked to Jay the other day. He walked me thru how to snip wires to an outdoor fixture but keep circuit going to other ones. 3 days later, I got an invoice in the mail, I owe him $150!


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