I am trying to install some rocker switches in my fishing boat to turn on nav lights and other accessories. I bought some led rocker switches (3-pole) from amazon and tried to install one to my fish-finder for starters. To ensure I installed the switch correctly, I watched a couple of YouTube videos similar to this one (https://www.youtube.com/watch?v=6ndOlIgn1ys).

As soon as I turned on the switch, it appeared to overload my battery (the battery was buzzing, and made a sound as if a fuse or breaker tripped). The battery was drained of some voltage pretty quickly. I was able to charge the battery back up.

These switches seem super simple to wire! What could I be missing???

To summarize:
1. I connected the switches middle pole directly to the positive terminal of the battery
2. I connected the switches accessory pole to the positive lead of my fish finder (through an in-line fuse)
3. I connected the switches ground pole to the negative terminal of the battery
4. I connected the negative lead of my fish finder to the negative terminal of the battery

Most of the videos I watched did exactly as I described above. Could I have a bad battery? I am able to wire the fish finder directly to the battery without any issues. Introducing the switch causes the overloading symptoms.

Any advice?

 

That was a single pole single throw switch not a three pole. (three terminals are not the same as three pole.) The two terminals grouped together in the video are "positive in" and "positive out". Actual location of those may vary with the manufacture. Always check the instructions with your switch.The third terminal was negative for the the light. It sound like you didn't identify the terminals correctly and connected the negative to one of the switch terminals causing a dead short. Negative goes to the the indicator light negative terminal.

 

Sorry didn't catch your update, before I responded.

My wiring and electrical vocabulary is lame, at best... Sorry!

Any way to easily identify the terminals, if they aren't labeled?

These are the switches I bought... http://www.amazon.com/AutoEC-Yellow-...ilpage_o04_s00

They aren't labeled as the pictures lead you to believe.

Thanks!

 

Maybe a simpler question that might provide me some clarity is: With this single pole single throw switch (three terminals), and simple accessory wiring scenario, what would get connected to the negative terminal of the 12v battery?

 

Look at the two lower pictures on the Amazon site you linked to . The "load" terminal is center and connects to the fish finder or whatever. The top-most terminal noted as "earth" goes to the battery minus terminal and the "supply" terminal of the switch goes to the battery plus terminal.

 

I added a picture to Furd's excellent wiring description.

Just as an aside.... ALL wiring that is connected to the battery MUST be fused to protect the wiring. Nothing but the engine itself should be connected "un-fused" to the battery.

I've been in this field for many years.... and I can't tell you how many fires and fried wiring harnesses I've worked on resulting from un-fused wiring.

 

You guys all rock! I can't thank you enough! It totally makes sense to me now and it works like a charm!

The internet is an amazing place! Thanks to all, for taking the time to set me straight!

 

Glad you got it. Thanks for letting us know. You did install a fuse didn't you?

 

Yessir... I have a fuse on every accessory. Thanks!