[justjeffy]

My wife has me replacing all our 30+ year-old toggle switches with rocker ones "because she likes the way they look". But, that's a completely different topic.

My problem is that I am replacing an old 4 way switch and the old switch doesn't have different terminal colors so I have no way to know which two poles are the common ones. None of the wires are marked. If I remove the old switch, is there a way to test the old switch to figure out which poles are the common ones?

During my replacements, I have found that some of my old switches are not consistent with the newer ones as far as common and traveler pole placement, so I was reluctant to just wire them to the same poles on the 4-way.

 

[Datawise]

The is no common on a 4-way.

You need a proper electrical tester.

Cheers
John

 

[justjeffy]

Perhaps my terminology is incorrect. However, there are two brass-colored contacts on the left side of the switch and two black-colored contacts on the right side of the new switch. Those terminals are all brass-colored on the old switch. I guess my question is (And I do have an electrical tester); can you explain how to test the old switch to know how to properly wire the new one??

 

[Bud9051]

hi Jeffy and welcome to the forum. data is correct, no commons as you would see on a 3-way.

Do you have a meter, you can test to determine the in and out for the travelers. ones I have installed have pairs on the sides so a pair going in either passes through to the pair going out or gets switched.

If you have a meter i can talk you through testing.

Bud

 

[jbfan]

Look at the connections printed on the box. They will show you how to wire the new switch.

On the old switch, note which pair of wire come out of the same sheath.

 

[justjeffy]

Hi Bud & JBfan

Yes I do have a tester. I am assuming that according to jbfan if I can identify the sheaths, then I just need to keep the two wires in each sheath attached a different side? The wiring diagram shows input on one side and output on the other. https://images.homedepot-static.com/catalog/pdfImages/2c/2ca5fdf8-c53b-4097-a7e8-59236f5311e4.pdf

 

[Bud9051]

That should do it.

Bud

 

[Datawise]

The 4-ways will normally have two sets of wires coming from each cable. There are many different options for this, but the most basic is there are two cables with white / black / red each. Normally the whites would be connected together and put into the back of the box; so that leaves you with blacks and reds from each cable.

Each conductor is paired with the other (blacks / reds) through the switch. In reality it does not matter because when you toggle the switch they flip / flop.

This shows a typical 4-way, but you need to test to see how the terminals are connected using your tester. Manufacturers' do not make there switches the same, so even after 30 years I still check a 4-way switch for operation.

You should get continuity between two sets of terminals in one position and a different set in the other position. Note the solid lines in each image.

There is no "off" position.

Cheers
John

 

[AllanJ]

Hmmm.

Looking at the diagram above... Using your continuity tester or ohmmeter (or multimeter set to ohms or resistance) ...

If all 4 terminals look the same then pick one and mark it with a black Sharpie or Magic Marker. Using your meter you should find that you get continuity (or nearly 0 ohms) from this terminal to two of the other terminals one at a time depending on the switch position and never with the third. Mark the third with the Sharpie.

Now connect the two travelers coming out of one cable to the marked terminals and connect the two travelers coming out of the other cable to the two unmarked terminals.

Unfortunately it is too often that which colors the travelers are are incorrect. You wil have to figure that out yourself, or remember which two were connected to the old switch. (Neutral coming through the box must be white.)

For a 4 way switch, you can think of one of the wires out of each cable as "the common wire" and it is not connected to the switch.

Never try to measure ohms or continuity with power turned on.

 

[justjeffy]

Thanks to all that responded. I took JBfan's suggestion and followed the pairs to each sheath. Then I used the diagram provided from the new switch to connect each side to one sheath. Not sure if I was lucky or did it right, but the switch works perfectly.

NOTE: It was good that I checked here first since the old switch was NOT wired the same as the new one despite both being from the same manufacturer.

 

[seharper]

My wife has me replacing all our 30+ year-old toggle switches with rocker ones "because she likes the way they look". But, that's a completely different topic.

Yeah, "changing switches and outlets" is like "doing your own oil change". It seems like an obvious and easy starter job for someone just learning... but it turns out to be pretty messy.

NOTE: It was good that I checked here first since the old switch was NOT wired the same as the new one despite both being from the same manufacturer.

You mean, "the terminals weren't in the same physical position on the old switch vs. the new"? That's completely normal for all 3-ways, and pretty much, all switches.

The manufacturers randomize the location of the black and brass screws on every switch. I bet if you went to a 3-way production line and plucked 5 in a row off the line, the screws would be in different locations on every one lol.