I have 4 LED lights that are 12v DC and 15 watts each = 5 amps. I want to wire these with two 3 way switches. I was thinking of some cheap spdt without the middle position of switch. Do you feel I need a relay? Would it be cheaper to use a relay due to the amp's? Also, I never wired something like this before. What relay to get and how do I wire this...sorry I am really new to all of this but it interests me alot. I would really appreciate if someone could forward me to a good previous post as I tried searching and it doesn't come up with this question. A diagram would be really cool. Best and cheapest way. Thanks again and I hope to be on this forum a lot in the future.

 

How do want the leds to work, all on at once,? or one at a time? each led is taking 1.25 Amps.

 

There is no such thing as a SPDT switch without the center contact, besides you would need it whether you choose to use a relay or not.

The choice between using switches/lines to carry the current or a relay would depend on how far you need to run the lines and where the power supply in located.

EDIT:

You could also just use a standard AC 3 way system and simply turn on and off the power supply.

 

Two possible configuration diagrams.
Steve G

 

You forgot the one with the relay.

 

Well I said two possible.

 

All four lights on one with either switch operating them. I would rather use the low voltage wire for the switches as it will be exposed. The length of the wires would be around 15 feet on one end and like 10 feet to the other from one power supply. What gauge 18 for wire? thanks again for those that have responded - a wiring diagram would be great of a relay if I need one....I want either switch to turn on all of the lights.

I really appreciate it. Very welcoming.

 

Sorry I meant a switch SPDT that doesn't have a middle position...if that makes sense. So just on or off.

 

The two difference switches are SPDT and SPDT-centre off.
Also the wording for the switching method is dependent on what part of the world, it is mainly 3 way in N.A., most other places it would be termed two way.
Max.

 

All four lights on one with either switch operating them. I would rather use the low voltage wire for the switches as it will be exposed. The length of the wires would be around 15 feet on one end and like 10 feet to the other from one power supply. What gauge 18 for wire? thanks again for those that have responded - a wiring diagram would be great of a relay if I need one....I want either switch to turn on all of the lights.

I really appreciate it. Very welcoming.

 

You can’t make a 3 way system without the proper switches.

Sounds like you want something like GopherT has posted, which will require two 20 amp relays, or perhaps you could use a pulse-on pulse-off relay, and 2 momentary SPST switches.

But I would advise using standard SPDT switches and a single HD relay.

And you probably want to use at least 16 gauge for the loads and 18 for the relay.

 

You can’t make a 3 way system without the proper switches.

Sounds like you want something like GopherT has posted, which will require two 20 amp relays, or perhaps you could use a pulse-on pulse-off relay, and 2 momentary SPST switches.

But I would advise using standard SPDT switches and a single HD relay.

And you probably want to use at least 16 gauge for the loads and 18 for the relay.

How do you get to 20 amps relays? He can put the LEDs in series and use a 15V supply - then a 1.5 to 3 amp Relay will be fine.

 

You don't need a relay for 25 ft. ,16 gauge wire is sufficient. Use my diagram for 3 way DC switching. I'm sorry GopherT but that schematic doesn't represent the OP's set up.
Steve G

 

How do you get to 20 amps relays? He can put the LEDs in series and use a 15V supply - then a 1.5 to 3 amp Relay will be fine.

"I have 4 LED lights that are 12v DC and 15 watts each = 5 amps."

Therein lies the confusion.

If the total is only 5 amps and the LEDs can be placed is series, why the concern about current?

Four 12 volt LEDs can't be placed in series and run @ 15 volts...

 

 

Relay option.

 

You're wasting your time...he says he doesn't want to use a switch with a common pin...

 

See post #8

 

Ok, no center off position.

A switch type that has no place in a 3 way setup anyway, unless you want to disable the other switch.

I need more practice reading other peoples posts, I will admit that.

 

The circuit in post #4 would work for what you want, if you replace the load with an appropriately specced relay.

The relay operating voltage can be anything. You could drive it with 12VDC and use automotive relays.

The switched current rating required depends on what you have to power the LEDs. The contacts can be rated at 5ADC if the LEDs are wired in series. But then you’ll need a 48VDC supply. If they are wired in parallel, you’ll need a 12VDC supply, rated at 20A.

I’m assuming these are 12VDC modules and hence have current limiting built in.