3 way 12 v light switch

[rwells36]

I am trouble shooting a light switch in a guest stateroom that is also controlled by a switch in the companionway.

The switch in the stateroom has 3 wires (green, white and black). All three wires are to be inserted into the rear of the switch face (see photo). My question is if the color(s) correspond to the numbers (again see photo).

Thanks!

[transmitterdan]

Originally Posted by rwells36

I am trouble shooting a light switch in a guest stateroom that is also controlled by a switch in the companionway.

The switch in the stateroom has 3 wires (green, white and black). All three wires are to be inserted into the rear of the switch face (see photo). My question is if the color(s) correspond to the numbers (again see photo).

Thanks!Attachment 136182

Unless you have a wiring diagram for that boat there is no way to tell by the colors what is what. Assuming you can measure DC voltages with a volt meter there is something you can do to figure it out. In all cases the negative lead of the volt meter should be connected to the boat DC minus bus. Do not connect the minus lead of the meter to any of the 3 wires.

Measure and write down the voltage on all 3 wires with the companionway switch in both positions. So you will make 6 total measurements, 3 in one position and 3 in another position. If you tell me what these 6 voltages are then I can tell you how to wire up the stateroom switch.

[moctrams]

https://tse1.mm.bing.net/th?&id=OIP....9&rs=0&p=0&r=0

[a64pilot]

Three way switches drive me Ape ****. I just keep changing it around until it works, never have understood the things

[DeepFrz]

How is this?

[rwells36]

Originally Posted by transmitterdan

Unless you have a wiring diagram for that boat there is no way to tell by the colors what is what. Assuming you can measure DC voltages with a volt meter there is something you can do to figure it out. In all cases the negative lead of the volt meter should be connected to the boat DC minus bus. Do not connect the minus lead of the meter to any of the 3 wires.



Measure and write down the voltage on all 3 wires with the companionway switch in both positions. So you will make 6 total measurements, 3 in one position and 3 in another position. If you tell me what these 6 voltages are then I can tell you how to wire up the stateroom switch.

Switch ON Green 0 volts, Black 10.5 volts, White 0 volts

Switch OFF Green 0 volts, Black 0 volts, White 10.5 volts

Note: black lead from the volt meter was connected to the boats grounding system under all 6 readings.

[transmitterdan]

Originally Posted by rwells36

Switch ON Green 0 volts, Black 10.5 volts, White 0 volts

Switch OFF Green 0 volts, Black 0 volts, White 10.5 volts

Note: black lead from the volt meter was connected to the boats grounding system under all 6 readings.

Ok, now we can figure this out. This is how you hook up the switch:

Green - 0 (goes to the light)
Black - 1 (comes from the companionway switch)
White - 3 (comes from the companionway switch)

If you don't like the position of the switch you can swap the black and white wires. It really doesn't matter which way they go the switch will still work.

[rwells36]

BINGO!!! Thanks

[buzzstar]

Originally Posted by rwells36

BINGO!!! Thanks

Gosh, how refreshing. A direct question and an actual resolution. I learned something too as a simple(ton) reader of the posts. Am additional "thanks" to all.

[captainwireman]

Originally Posted by rwells36

Switch ON Green 0 volts, Black 10.5 volts, White 0 volts

Switch OFF Green 0 volts, Black 0 volts, White 10.5 volts

Note: black lead from the volt meter was connected to the boats grounding system under all 6 readings.

Let's get the terminology right so it will sound like you know what you are talking about. It is not an on/off switch (single pole single throw). It is a proximity switch. It depends on the position of the other switch to determine whether or not the device will be on. You are using single pole double throw (SPDT) for a three way application. Useful to know because you can find tiny, discrete little microswitches on line that make for a nice, custom install

[ebs001]

Originally Posted by rwells36

I am trouble shooting a light switch in a guest stateroom that is also controlled by a switch in the companionway.

The switch in the stateroom has 3 wires (green, white and black). All three wires are to be inserted into the rear of the switch face (see photo). My question is if the color(s) correspond to the numbers (again see photo).

Thanks!Attachment 136182

Check the wiring on the other three way switch. The wires will be exactly the same on both switches.

[rwells36]

Originally Posted by ebs001

Check the wiring on the other three way switch. The wires will be exactly the same on both switches.

I did. They aren't the same.

[rwidman]

Originally Posted by rwells36

Switch ON Green 0 volts, Black 10.5 volts, White 0 volts

Switch OFF Green 0 volts, Black 0 volts, White 10.5 volts

Note: black lead from the volt meter was connected to the boats grounding system under all 6 readings.

Unless you have a 10.5 volt battery, you have other issues that need to be dealt with.

The good news is, your bulbs will last a very long time.