I need to get a relay for heated grips, which one do I get?

[discgolfdude]

Ok, so I installed my oxford heated grips, and I left them on by mistake, and the battery died. So, to prevent this from happening again, I want to connect them to my ignition wire, or to my headlights. The problem I am having is which relay type do I need? I went to Shucks today, and I noticed that there are a lot of relay types and styles. So which one do I need?

 

[CHEMIKER]

I haven't wired it yet, but I got a 30 amp 4 prong relay from the auto parts store based on Motogiro's recommendation.

 

[Motogiro]

Here's a circuit I whipped up. http://www.600riders.com/forum/fz6-mods/35862-got-heated-grips-finally.html

Any relay that can has a contact current rating higher than what you require is good. You want a relay with a 12 volt DC coil. There are a ton of 30 amp automotive type relays you can use for your application. You won't need anywhere near 30 amps but this is a common easy to get relay. You could go to Radio Shack and get their 10 amp relay and buy the plugin socket that goes with it. That way if the relay goes bad you just swap it out instead of a hard wired set-up.

 

[discgolfdude]

Thanks, but what I was wondering is, do I need a 5 prong or a 4 prong relay?



looks like I need just a 4 prong relay! But there are so many size and shapes to get.

 

[Motogiro]

Thanks, but what I was wondering is, do I need a 5 prong or a 4 prong relay?



looks like I need just a 4 prong relay! But there are so many size and shapes to get.

What you want is just a 4 prong. You'll be using a normally open contacts. That will be 2 of the prongs and you will have a 12 volt coil in the relay that will be the other 2 prongs.
You might see a relay with 5 prongs and that has a normally open and normally closed contact set. You can use that type and you will just use the normally open configuration without using the normally closed.

What normally open means is that the contacts don't pass current unless the relay coils is energized.

What normally closed means is that the contacts are passing current unless the relay coil is energized.

Relays can also have additional poles which means they can switch more than one circuit at the same time in different open or closed combinations.

Basically you want a single pole, single throw, normally open relay with a 12 volt DC coil. The most common ones I run into for automotive are those 30 amp deals which will be more than enough for your grips.

 

[discgolfdude]

I'll look for it tomorrow, thanks Cliff