Help with an logic-OR type wiring setup

[denno]

I am looking to wire up some lights in a way where one set of lights are on when they're being fed power, however if the other line of lights become active, the first line will turn off, and stay off while the other line is on, but when that other line goes off again (and there is still power to the first line), then the first line will activate.

I'm wiring up some LED globes in my car which is a dual circuit (white and orange leds), so I want it hooked up to that when my parkers circuit is active, the white LED's will be on (this I know how to do), however when I flick the indicator, I need for the white LED's to be off whilst the orange is on (so that the orange isn't competing with the white in the headlight assembly).

I thought the globes that I bought did this automatically inside the globe, but they don't so I need to work out how to do it myself.

Thanks
Denno

 

[Boncuk]

Hi Denno,

a logic OR-gate works with two inputs and one output. If inputs are low the output is low. If either input (or both of them) is high the output is high.

That's not the kind of logic you need for your project.

Please make up a sketch how the LEDs should be lit.

Boncuk

 

[Brevor]

You could use a SPST switch for the white led's and a DPDT switch or relay for the orange led's.

 

[denno]

Yeah I was thinking of a relay, but I was hoping there was something smaller that I could use.. I thought that using a normally closed relay, with the indicator wire hooked to the signal of it, opening the relay when it's active, therefore giving the desired effect upon the white LED's.

Boncuk, I'm working on the sketch now.

 

[Gary B]

Brevor is correct, you only need a SPST center off switch. Connect the center contact to power. Connect the upper contact to white lamp input and the lower contact to Orange input. If you flip the switch up you get orange, down gets white and center position is off. You can find them at Radio Shack.

 

[denno]

Brevor is correct, you only need a SPST center off switch. Connect the center contact to power. Connect the upper contact to white lamp input and the lower contact to Orange input. If you flip the switch up you get orange, down gets white and center position is off. You can find them at Radio Shack.

Thanks, but this isn't the aim of what I want. I will be turning the white LED's on via my headlight switch (turning the headlights on), and I will be powering the orange via my indicator stalk. So using a new switch isn't going to help...

 

[denno]

Here is a sketch of how it will be wired. It's very simple, like very very simple..

**broken link removed**

 

[ronv]

Flasher

A small automotive relay is probably the easiest. Alas, one for each side.

 

[denno]

Ok cool, thanks. As I said I was hoping to do it with smaller components, but that's alright, I'll just get a couple of relays. Probably be the easiest option anyway.

Thanks all. I'll post back with the results .

 

[denno]

Bought a couple of change over relays today so I can utilize the normally closed function. Here is the result (using my bench top power supply for now)

I'm going to post a quick schematic to show how I've hooked it up, so people can check to make sure there won't be any feedback issues or anything..

Thanks

 

[mbarazeen]

you can use a 4011 NAND gate IC and a transistor too for the purpose. power to orange is inverted to enable the drive transistor of white ones.