I have the same issue he does - my 4 way system (3 switches, 1 light) has 48 volts across the black(hot) and white(neutral) - there is NO LOAD (no LAMP connected) just my meter. I have a 3 way circuit that measures just like I would expect it to. I have no triacs in the circuit so from the other comments about reactance in the circuit - I am not following where that would come from. Since I can see the path of the wiring, I can't buy into inductance either. Somebody have a real answer, I know that sometimes a bad neutral can cause an issue, so I am wondering if the neutrals are somehow crossed on the 4 way and the 3 ways are switching the hot. I have not pulled the switches out of the wall to verify - but was hoping someone could just say hey that is an issues with this or that - and I can go right to it with out having to really isolate each of the wires and draw out the diagram of the connections - because the way things look now - I will need to draw the diagram of how it is wired to make sure it is correct (it probably is not) I have found other simple cross up of wiring in the house so it would not surprise me.
Why do I have voltage when switch is off?
- Thread starter Randyj
- Start date
Users who are viewing this thread
I have the same issue he does - my 4 way system (3 switches, 1 light) has 48 volts across the black(hot) and white(neutral) - there is NO LOAD (no LAMP connected) just my meter. I have a 3 way circuit that measures just like I would expect it to. I have no triacs in the circuit so from the other comments about reactance in the circuit - I am not following where that would come from. Since I can see the path of the wiring, I can't buy into inductance either. Somebody have a real answer, I know that sometimes a bad neutral can cause an issue, so I am wondering if the neutrals are somehow crossed on the 4 way and the 3 ways are switching the hot. I have not pulled the switches out of the wall to verify - but was hoping someone could just say hey that is an issues with this or that - and I can go right to it with out having to really isolate each of the wires and draw out the diagram of the connections - because the way things look now - I will need to draw the diagram of how it is wired to make sure it is correct (it probably is not) I have found other simple cross up of wiring in the house so it would not surprise me.
ActionDave
Electrician
The answer is in the post you quoted....... if you are testing with a digital meter you will get some voltage readings every time you check a three or four way switch.
If you want to know if the 48V is real you need to check with an analogue meter or a digital meter with a lo Z setting. You can get an analogue meter from Blowes or Home Desperate for less than thirty dollars, just be careful that you use it on the right scale.
Sponsor
Paid Advertisement
I do not know if I have my old analogue meter, but someone at work has a lo z, but Lo Z and analogue meters are typically used when dealing with a triac type circuit, where you have low impedance [Lo-z].
Given the wires come in from the panel to switch 1, then to switch 2, then switch 3 and then to my two wires for the light assembly, and it is a direct route where they do not run across other wires, I am wondering how it would be possible for the voltage to be there like this.
My 3 wire setup is like this but has 0 volts - and I would expect it to have more probability of induced voltage given the run, and run length.
I could tap the leads together and see if I get a spark or trip a breaker
, but I guess I need to invest in a cheap analogue meter if I can't find my old radio shack special.
Given the wires come in from the panel to switch 1, then to switch 2, then switch 3 and then to my two wires for the light assembly, and it is a direct route where they do not run across other wires, I am wondering how it would be possible for the voltage to be there like this.
My 3 wire setup is like this but has 0 volts - and I would expect it to have more probability of induced voltage given the run, and run length.
I could tap the leads together and see if I get a spark or trip a breaker
, but I guess I need to invest in a cheap analogue meter if I can't find my old radio shack special.
Jadnashua
Retired Defense Industry Engineer xxx
Wires running next to each other can induce a voltage in adjacent ones. That does NOT mean that there is enough current to cause any problems. A modern digital multimeter can have a megaohm per volt input impedance or more and puts essentially NO load on the circuit. An old analog meter has MUCH less input impedance (millions of times less), and acts more like a short, bleeding off that induced voltage. Using an analog meter in an electronic circuit can change the characteristics of it, and there, a digital one is better since it 'looks' like it essentially isn't there.
Similar threads
