K O Posted February 13, 2014 Share Posted February 13, 2014 Our house came with a 5-way switch that controlled lights on the stairs for 4 floors. We broke up the 5-way switch using Insteon switches and in-line linc dimmers in the light fixtures to make a 4-way switch and a 3-way switch. We've got everything working well, but I think there may be an issue with the wiring that is unsafe. To better explain what the original setup looked like, here's the 4-floor house setup from the bottom to the top. Garage (lowest level) - There is a switch at the bottom of the stairs leading up to the main level. Main level - There are 2 switches, one at the top of the garage stairs leading down (the switch is physically in the garage), and another switch for the stairs leading up to the mid-level. Mid-level - There is a switch. Top-level - There is a switch. The builder thought it best to wire up the garage lights with the house stair lights. At face value, this seems okay - if you're coming home and it's dark, one switch will turn on the lights for all the stairs. But if person A is working in the garage and person B is inside walking up the stairs, person B might turn the lights off, leaving person A in the garage in the dark unexpectedly, or vice versa. This is simply not well thought out, and we've successfully changed it using Insteon switches. We replaced all 5 switches with 2477D dimmer switches, and each light fixture has been re-wired with In-LineLinc Dimmers. We set them up in groups such that the main house stairs (3 switches) illuminate only the interior lights, and the 2 garage switches only illuminate the lights in the garage. The problem I have is with the wiring. There is one traveler wire in each of the very top and lowest switches and the other 3 switches have 2 traveler wires each. In my switches, I wired all the blacks together and all the whites together, and simply capped off the traveler wires thinking they will no longer be needed or used. The problem I have is that the traveler wires at every single one of the 5 boxes are showing 25 volts when tested across either the neutral or ground. I don't think there's an open neutral as neutral/ground shows 0 volts, and all the black/white connections show 120 volts with no issues. I'm not an electrical expert, so I'm here asking why is there ~25 volts across the red traveler wires when they aren't wired into anything? What could they be getting current from? Have I grossly misunderstood how this 5-way setup was wired? I have double and triple checked every connection ensuring it is carefully pigtailed, good contact is made, and the voltmeter shows 120 volts where it should. Any thoughts? I don't want to risk burning my house down, and local electricians either want $500+ to look at it or scoff at my whole-home Insteon setup like I'm some kind of animal for thinking outside the box. Link to comment Share on other sites More sharing options...
gatchel Posted February 13, 2014 Share Posted February 13, 2014 My guess would be Phantom voltage. http://www.electriciantalk.com/f2/phantom-voltage-8522/ Link to comment Share on other sites More sharing options...
Brian H Posted February 13, 2014 Share Posted February 13, 2014 If all the travelers are capped off and not used. There is some very small capacitive coupling between the wires and the small voltage would only be read on a high impedance meter. So your meter is probably reading a phantom voltage as pointed out. If you want to double check it. Use a 330K resistor from the traveler to Ground or Neutral and measure it again. The voltage will be much lower if it is a phantom reading. Link to comment Share on other sites More sharing options...
K O Posted February 13, 2014 Author Share Posted February 13, 2014 If all the travelers are capped off and not used.A high impedance meter is probably reading a phantom voltage as pointed out. If you want to double check it. Use a 330K resistor from the traveler to Ground or Neutral and measure it again. The voltage will be much lower if it is a phantom reading. Thank you both for your ideas. This is new territory for me. In the now 15 minutes I've been reading this 'phantom voltage', I am understanding that possibly because the traveler wire is in the same sheath as the hot wire that the magnetic field around it is causing the unused traveler wire to have 25 volts? I think I understand this idea, but I don't see how it explains why testing the neutral/ground doesn't also show 25 volts - aren't those wires are also in the same shielded jacket being exposed to the same magnetic field? I will try getting a 330k resistor and wiring it between the disconnected travelers and ground as you've suggested. As someone with very limited knowledge in this field, why would the 330k resistor show a much lower voltage if it's phantom voltage? Link to comment Share on other sites More sharing options...
apostolakisl Posted February 13, 2014 Share Posted February 13, 2014 It depends on what, if any connections you have to your neutral/ground. If they are both connected to your panel, then they will have zero potential since the two are connected to each other at the panel. If neither are connected to anything at either end, then they won't have any potential between them since any induced potential from running next to your hot will be equal in both and zero out (assuming they are both in the same outer jacket). Also, you should not have any "phantom voltage" on a wire running next to a hot wire if that hot wire has no current running through it. In other words, you have to have an operating load connected to that hot for a nearby wire to pick up an EM induced voltage. Link to comment Share on other sites More sharing options...
K O Posted February 14, 2014 Author Share Posted February 14, 2014 It depends on what, if any connections you have to your neutral/ground. If they are both connected to your panel, then they will have zero potential since the two are connected to each other at the panel. If neither are connected to anything at either end, then they won't have any potential between them since any induced potential from running next to your hot will be equal in both and zero out (assuming they are both in the same outer jacket). Also, you should not have any "phantom voltage" on a wire running next to a hot wire if that hot wire has no current running through it. In other words, you have to have an operating load connected to that hot for a nearby wire to pick up an EM induced voltage. I'm not sure how to setup a condition where the hot wire has no load - I have Insteon switches and they draw a constant albeit low current from every switch on the circuit. Suggestions? Anything better than removing every Insteon switch and then testing again? Link to comment Share on other sites More sharing options...
Brian H Posted February 14, 2014 Share Posted February 14, 2014 Try the resistor and see what the 25 volts reads. I suspect it will be very low or close to zero volts. You will not have to keep the resistor on the travelers all the time as it is just a stray voltage with no current capabilities. Link to comment Share on other sites More sharing options...
oberkc Posted February 14, 2014 Share Posted February 14, 2014 I'm not sure how to setup a condition where the hot wire has no load - I have Insteon switches and they draw a constant albeit low current from every switch on the circuit. Suggestions? Anything better than removing every Insteon switch and then testing again? Yes, insteon switches draw a small amount of power, even when "off". However, most insteon switches have the little tab that one can pull out to completely remove power from the electronics. Have you tried that? Put an incancescent light bulb between traveler and ground. Does it light up? Is there voltage when the bulb is present. If no, and no, I would not worry about it. Link to comment Share on other sites More sharing options...
Brian H Posted February 14, 2014 Share Posted February 14, 2014 Incandescent light bulb load sounds like a good way to go. You don't have to search out a resistor. Link to comment Share on other sites More sharing options...
K O Posted February 14, 2014 Author Share Posted February 14, 2014 Put an incancescent light bulb between traveler and ground. Does it light up? Is there voltage when the bulb is present. If no, and no, I would not worry about it. Thank you, all. I will try that! Link to comment Share on other sites More sharing options...
apostolakisl Posted February 14, 2014 Share Posted February 14, 2014 It depends on what, if any connections you have to your neutral/ground. If they are both connected to your panel, then they will have zero potential since the two are connected to each other at the panel. If neither are connected to anything at either end, then they won't have any potential between them since any induced potential from running next to your hot will be equal in both and zero out (assuming they are both in the same outer jacket). Also, you should not have any "phantom voltage" on a wire running next to a hot wire if that hot wire has no current running through it. In other words, you have to have an operating load connected to that hot for a nearby wire to pick up an EM induced voltage. I'm not sure how to setup a condition where the hot wire has no load - I have Insteon switches and they draw a constant albeit low current from every switch on the circuit. Suggestions? Anything better than removing every Insteon switch and then testing again? You can pull the tab on the Insteon switches and that shuts them off. But the amount of current an Insteon switch pulls is not going to have a measurable affect on adjacent wires. I have seen the 25v thing myself before and it has always proved to be false or "phantom", capable of producing no measurable current. Link to comment Share on other sites More sharing options...
apostolakisl Posted February 14, 2014 Share Posted February 14, 2014 Incandescent light bulb load sounds like a good way to go.You don't have to search out a resistor. Most multi-meters will let you measure current across 2 wires. Of course you wouldn't do that if there was the possibility of a large current. I really don't think this situation is going to make any current or at least anything more than micro-amps. If the fuse on the multi-meter blows, then that means I was wrong. Link to comment Share on other sites More sharing options...
Brian H Posted February 14, 2014 Share Posted February 14, 2014 I have used the current method to verify it is a phantom voltage. Link to comment Share on other sites More sharing options...
larryllix Posted February 14, 2014 Share Posted February 14, 2014 The old mechanical low-impedance solenoid testers were the best for eliminating induced voltage indications from parallel live wiring but the micro current available would not be indicated and some people, like myself, would react badly to it while others could not feel it no matter how hard they grabbed the conductor. Induced current requires a current in the adjacent wire and a loop or return path in the receiving conductor under test. Link to comment Share on other sites More sharing options...
ELA Posted February 15, 2014 Share Posted February 15, 2014 The "so called phantom voltage" in this situation is not an EM effect. Therefore there is no load current required to measure an "induced voltage" on the red wire. It is a capacitive coupling issue. The level of measured voltage can be explained by a simple resistor divider "equivalent circuit". Try connecting a 120Vac source to 3 wire cable with 120Vac applied to hot and neutral. No need to have a load connected from hot to neutral. Use a high impedance meter to measure from Neutral (or ground) to the "open circuit" Red wire. You will measure a voltage that is in direct relation to the relative impedance's of the capacitive reactance between wires to the the meters impedance. The longer the cable the more dangerous the "coupled" voltage may be. Phantom or ghost voltage is a popular term but it is a very real voltage, just happens to be from a high impedance source. Link to comment Share on other sites More sharing options...
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