WS200+ with 118vac out from neutral.

[Ryanb]

Hey hoping someone can help. I have installed over 40 of the dimmer and non-dimming switches in this building. I also have Re-wired the entire building. This is not my first time completing electrical work, but I am stumped.

Ok so I have a bank of three switches in a triple gang box. When I was wiring in the first light fixture I checked for voltage on the hot and there was nothing.

I proceed to strip the neutral and ground and I get a nice zap from the neutral... So I retraced every wire and connection. The voltage was clearly coming from the switch.

So I removed all the wires from the switches to check for internal shorts. There was no connectivity between any of the poles.

I continued troubleshooting by only connecting the line and tested each of the three switches. Each switch presented 118 vac neutral to ground without the neutral or load wires connected. Every other switch in the building shows zero or near zero volts neutral to ground.

So the questions are;
Are these switches bad?
What would cause the switch to connect 118vac out to ground?

I am afraid to wire in another new switch until I understand what happened. It seems so strange that three switches were all bad in the same way, on the same circuit as other switches that are fine all at the first time being energized.

Thank you in advance!!

[Guest]

My suspicion is that another switch/outlet/gang box on that same circuit as your problem switch(es) is miswired. Time to figure out what else is on that circuit!

[ewkearns]

An open neutral. Reverse wired GFCI? Try to determine if it is the neutral or the ground that is hot. Also, did you wire any sub-panels? Backtrack from the offending box to the main panel.

[Ryanb]

So I already checked all the circuit and found the source was the actual switch. I took the bank of three switches out and the neutral was zero volts again.

Then I attached the line voltage to the line voltage terminal and tested the neutral terminal when only the line voltage was hot. The neutral was passing ask the voltage out. The neutral was not connected to the building wires, the only thing connected was the hot wire.

The rest of the building wires tested normal .

[outbackrob]

I had something similar happen in our old house. SMALL metal gang boxes. Shorted a switch connection to the box. Got voltage when/where I wasn't expecting it. I now wrap the switches in electrical tape.... Not implying that you have the same situation, but it is most likely a wiring mistake/issue. Put new eyes on it. It's there.

[Ryanb]

Here are some photos of the situation, more on the next post

[Ryanb]

Here are the other voltages, everything is correct on the building side... The switch is just acting funny

[keepersg]

An older style of wiring was to bring power and neutral to the junction box where the light fixture was installed. Then 14/2 would be run to the switch box with one wire carrying power to the switch and the other wire back to the junction box to complete the circuit when the switch was closed. A real pain for installing any automated switches that require a neutral. Don't know if that's the problem but I would check in the junction box for the lights or whatever these switches control to examine the wiring.

[Ryanb]

Yeah unfortunately I just re-wired the entire building all with fresh THHN in conduit. I can get to every wire and connection. The electrical all is permitted and I am very familiar with code... Not trying to be the new guy who says he knows everything, just that this electrical system is well designed not a crappy remodel of a remodel.

All I can guess is that the switch has an error state that behaves in this manner after something happened. For example if one of the common/ neutral wires was not fully connected in the inbound circuit and the switch was energized, would that cause the switch to fail like this?

It is virtually impossible for there to be 100% failure from the factory on three random switches, so there had to be something that caused them to want to send voltage out the neutral lug. But there is not an internal short with the switch completely disconnected from the building, so it seems like it has to be a software or electronic issue in the switch.

[drhtmal]

As a test hooh any extension cord to line and neutral and do your test. Plug it into a different known working outlet. It the problem persists it is the switch, if the problem stops it is the wirimg.

[ewkearns]

Assuming the exact same ground wire and common wire are used and the switch is either off or on in both scenarios and "same side up"...

and you are getting 0V from Ground to Common, and

you are getting ~120V from Ground through the Switch to the Common, with no hot attached, WHERE is the difference in potential coming from?

The only thing that changed is the switch and it can't be creating the potential by itself, not without a hot that isn't colored black.

[outbackrob]

Take one of the switches in question and swap it out in a circuit you know is functioning correctly. If it works, that's another indicator that the wiring is at fault somewhere. If it causes the same issue, that's another indicator the switch is the cause. It doesn't yet prove anything, but it doesn't risk another switch from going bad.

[Ryanb]

Ok so the good news is that they work now... The bad news is that there is a very dangerous hazard to these switches.

My problem was that one of the inbound white neutral wires was not fully connected so the switch didn't receive a connected neutral.

In that state the switch dumps voltage out on the neutral circuit. If you happen to drive a nail it otherwise sever the inbound neutral to the switch, both the neutral and hot wires will have line voltage!

This seems like a fire hazard and a very unsafe fail safe mode to go into if the neutral is not connected.

Homeseer engineers, why would you design them this way and is there a software patch to make these switches safe? I attached photos above showing the voltage state of each wire pair. I use blue for my lighting circuits line voltage.

[ewkearns]

See #3 above. Hallmark of an open neutral. Hopefully, you do not have any bonding screw in any sub-panel and that ground bars have been added as appropriate...

[Alex_W]

The switch is functioning properly. As others have stated, what you experienced is called an open (loaded) neutral. You would have gotten shocked no matter what the load was that you were working with (a light bulb, an appliance, whatever). In this case there are two loads in the circuit. One load is the light that is being controlled by the switch, the other is the switch itself (because it requires current to operate).



All loads "dump voltage out on the neutral circuit". That is how they are able to operate. There must be a flow of current between line and neutral. You got shocked because you inserted yourself into the circuit (you placed yourself in series with the load). Whenever any load in your house is on, there is potential on that circuits neutral wire. If you conducted the same test on any load (breaking the neutral connection and testing for voltage at the neutral wire leaving the load), you would get the same results. This is why one shouldn't work on live circuits and why one should always use a meter to confirm that no wires are carrying voltage before working on the circuit.

Do a search for loaded neutral or open neutral if you want more information.