3 way switch issue

AliceR

Member
Location
Waterloo, WI
Occupation
Electrician
Hello folks,

I am stumped on this one. I'm replacing some switches and plugs for a customer and I can't seem to wrap my head around the problem.

There is a 3-gang switchbox. One single pole that controls a porch light, and Two 3 ways that control lights in the kitchen, with their associated switches on the other end of the kitchen.

The wiring has been not great, lots of rat tailing, barely 2" of wire to work with etc.
I put in all new switches for that box, now I have a problem. The two 3 ways only work when the porch light is on. I kept wires in the same orientation as the old ones, EXCEPT for the single pole porch light had a wire on each screw AND one stabbed into the back of the switch which then rat tailed out to each other switch. What the hell.

Did they some how join up the switches using the single pole from the porch? I can't figure out how to fix this. Help!
 
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augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
My guess would be the problem is with the statement " I kept wires in the same orientation as the old one".
Often when 3 way switches are replaced the "common" (mfg marking) or darker terminal is in a different location from the switch being replaced. You need to determine which conductor is LINE and LOAD as opposed to travlers and be sure to put them in the common, dark screw and ignore orientation,.
 

AliceR

Member
Location
Waterloo, WI
Occupation
Electrician
My guess would be the problem is with the statement " I kept wires in the same orientation as the old one".
Often when 3 way switches are replaced the "common" (mfg marking) or darker terminal is in a different location from the switch being replaced. You need to determine which conductor is LINE and LOAD as opposed to travlers and be sure to put them in the common, dark screw and ignore orientation,.
Thank you for the advice. I will verify this. I appreciate it. :)
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Hello folks,

I am stumped on this one. I'm replacing some switches and plugs for a customer and I can't seem to wrap my head around the problem.

There is a 3-gang switchbox. One single pole that controls a porch light, and Two 3 ways that control lights in the kitchen, with their associated switches on the other end of the kitchen.

The wiring has been not great, lots of rat tailing, barely 2" of wire to work with etc.
I put in all new switches for that box, now I have a problem. The two 3 ways only work when the porch light is on. I kept wires in the same orientation as the old ones, EXCEPT for the single pole porch light had a wire on each screw AND one stabbed into the back of the switch which then rat tailed out to each other switch. What the hell.

Did they some how join up the switches using the single pole from the porch? I can't figure out how to fix this. Help!
You have simply connected the supply for the 3-ways to the switch leg of the single pole switch.
 

jmellc

Senior Member
Location
Durham, NC
Occupation
Facility Maintenance Tech. Licensed Electrician
Single pole switch had the main hot feeding it. The rat tail to the other 2 switches was a feeder to them, jumped off the SP. Splice your incoming hot to 3 jumpers, 1 for each switch. Less confusing to anyone later on and doesn't depend on a stab from back of the switch. What you did was jump the feeds from the load side of the switch, making the SP a master switch over the others.
 

kwired

Electron manager
Location
NE Nebraska
The extra wire stabbed into the back was in lieu of a pigtail.

It’s a Parallel hot feed to the kitchen lights.
regardless your feelings on back stabbing one has to look at what it connected to what.

The original screw terminal and back stab on same end of switch is a splice going three different directions if you draw a schematic of what you have there.

could have done similar with a switch that has pressure plate terminals that accept two conductors , though some people still prefer to make a pigtail so only one lead goes to each switch terminal. Nothing wrong code wise, just personal preferences here.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
could have done similar with a switch that has pressure plate terminals that accept two conductors , though some people still prefer to make a pigtail so only one lead goes to each switch terminal. Nothing wrong code wise, just personal preferences here.
I remember reading that you're not supposed to use both the screw and the push-in terminal to interconnect wiring, such as line in and out to continue a circuit.
 

kwired

Electron manager
Location
NE Nebraska
I remember reading that you're not supposed to use both the screw and the push-in terminal to interconnect wiring, such as line in and out to continue a circuit.
Not a fan of using the push in feature on these devices, but at same time I don't see how using the screw terminal would impact the push in connection in any way.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Not a fan of using the push in feature on these devices, but at same time I don't see how using the screw terminal would impact the push in connection in any way.
It was more about avoiding circuit current passing through the internal parts, from screw to push-in.

Hey. I found a pic showing what I'm talking about, although it's a receptacle instead of a switch.

I don't know whether the comments I remember applied to all devices or just switch terminals.

1708272365235.jpeg
 
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kwired

Electron manager
Location
NE Nebraska
It was more about avoiding circuit current passing through the internal parts, from screw to push-in.
I generally avoid the push in, but will admit in some situations with known low loading to push in a conductor vs pig tailing. And that was more likely for me to do back before LED lights became a big thing than it is now.
 

Seven-Delta-FortyOne

Goin’ Down In Flames........
Location
Humboldt
Occupation
EC and GC
regardless your feelings on back stabbing one has to look at what it connected to what.

The original screw terminal and back stab on same end of switch is a splice going three different directions if you draw a schematic of what you have there.

could have done similar with a switch that has pressure plate terminals that accept two conductors , though some people still prefer to make a pigtail so only one lead goes to each switch terminal. Nothing wrong code wise, just personal preferences here.


👍

I wasn’t actually making a comment either way on back-stabbing. Just trying to explain the circuit.
 

kwired

Electron manager
Location
NE Nebraska
👍

I wasn’t actually making a comment either way on back-stabbing. Just trying to explain the circuit.
Sort of same here initially. draw out the schematic of how things are connected and the back stab, the screw termination and one side of the switch are all tied to the same point - a splice that goes three different directions, and OP apparently did not put things back the same way they started out schematically.
 
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