Correct use of Pin 87a

Hi all.
Great forum, really helpful for someone like me (complete novice!)
So I had a question about wiring a light bar up with a trigger wire and a switch. I found my answer here: https://www.the12volt.com/installbay/forum_posts.asp?tid=143717#727647
Which has raised a new question for me. I thought I might have been able to wire the switch through Pin 87a. From the above post, that's not the way to go about it. So could someone please help me understand how Pin 87a should be correctly utilised?

Cheers

https://www.the12volt.com/relays/relays.asp

87a would not be used in your case. 87a and 30 are connected when the coil is not energized. When the coil is energized, 87 and 30 are connected.

87a would be used if you needed to open a connection.

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My ex once told me I have a perfect face for radio.

Still not sure I'm on this. As you stated, 87a and 30 are connected when there is no charge going through the coil. As such, my thinking was that if I could run a switch between 37a and the + of the light bar, I would be sorted. I realise this isn't the way to go now, but I just don't quite get the reasoning.

So wait- you're not using the switch to simply trigger the relay?

One of the main purposes of using a relay is to switch a larger amount of current than a typical switch can handle. As long as your switch is rated to handle the current required by the light bar, you could switch it through 87a. However, since you already have a relay, why not just use the switch to trigger it?

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My ex once told me I have a perfect face for radio.

I should clarify that the switch is a push button switch on the dash. At this point (wired as it is) the light bar comes on with my high beam, which is great for on the Rd. I want to be able to flick them on without the headlights though, mostly for camping purposes or if I just need more light without running all lights etc.

Is your push button a momentary switch (only on while button is pressed), or is it a mechanical latching switch (push once on, push again off)?

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My ex once told me I have a perfect face for radio.

Mechanical latching switch.

As long as it's rated to handle the current of your light bar, it would work through 87a from what you describe.

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My ex once told me I have a perfect face for radio.

Wow! I worked something electrical out!
I'm a little impressed, but that falls over when it just doesn't work. Not sure why and without going over it yourself. But your help has been greatly appreciated and I have those diodes on their way so will try that way and see if it works for me or not. Cheers and happy new year!