Switched receptical neutral?
- Thread starter elecold
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fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
Are you measuring the voltage with a high impedance meter? It is high impedance unless it says "low-Z".
if you use a low-Z meter you will probably see that these are phantom voltages (capacitively coupled) from the hot 120V wire for the other half of the receptacles.
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- Location
- New Jersey
- Occupation
- Journeyman Electrician
Are there lighted switches when in the OFF position?
elecold
Member
I came across an issue where I was getting 99volts on the switched receptical and 120 on the constant part of the receptical.
The rest of the outlets down the branch circuit line were 99volts also....
So I opened up the switched outlet. I discovered that in addition to the brass tab being removed the silver grounded tab was removed. (no pigtails obviously)
I replaced with a new receptical and removed just the brass tab. The issue was fixed.
Could it be that the other outlets that I had 120 volts on the switched and constant part were detabbed incorrectly also. :? Would the missing neutral tab explain the 15 volts on the dead switched portion?
The rest of the outlets down the branch circuit line were 99volts also....
So I opened up the switched outlet. I discovered that in addition to the brass tab being removed the silver grounded tab was removed. (no pigtails obviously)
I replaced with a new receptical and removed just the brass tab. The issue was fixed.
Could it be that the other outlets that I had 120 volts on the switched and constant part were detabbed incorrectly also. :? Would the missing neutral tab explain the 15 volts on the dead switched portion?
kwired
Electron manager
- Location
- NE Nebraska
We need more precise details of exactly what was where to be able to accurately answer that, but if you had the tabs broken off on the neutral side of receptacle - you probably had voltage issues - more like lack of voltage where it is needed in some places.
Otherwise assuming neutral is intact all the way through the circuit you can easily read a voltage on the switched circuit because of capacitive coupling. The fact the constant "hot lead" is in same raceway or cable with the switched lead creates a capacitor - a very weak one, but a typical digital meter with a high input impedance will measure this voltage and display it, a "low input impedance" meter will draw enough current just performing the test that it will "short out" this weak capacitor and you will not read any voltage.
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