Controlling LED tape with Rotary Switch

Projects General Guidance
1

Hi All,

I'm looking to turn strands of LED tape on using a 4 position rotary switch. I've taken on an existing project that currently does this by mains power. Though this is a perfectly fine way to do it, i'd like to use an arduino for stability.

My main issue is, i'm going to need to use more than one arduino due to the amount of LED tape used. Inevitably at some point there will be a crossover and i need a way for both arduino's to talk to each other. Is this possible?

Obviously depending on the position of the switch depends on what run of LED tape will turn on. Would this be done by connecting a pole from the switch to a pin on the Arduino then from a pin out on the Arduino to a relay then from the relay to the LED tape? Or am I completely missing something?

Am i off the mark on using an Arduino or should i stick with using the mains power?

Cheers
T

2

Inevitably at some point there will be a crossover and i need a way for both arduino's to talk to each other. Is this possible?

Yes it is possible but no you don't have to use more than one. Indeed it would be a very silly thing to do.

Or am I completely missing something?

You are missing the fact that you have not mentioned what sort of LED strip you have. Their are quite a few different types and they all need handling differently.

3

I'd be using somewhere around 70 strands of tape all needing to run off a separate relays, that could be done off of 1 mega?

I'd be using 24v single coloured tape so i'd only need to power it on/off.

4

You can do that off a single Uno if you wanted by using port expanders or shift registers.

5

How many LEDs on each tape?

You may be able to use tpic6b595 or tpic6a595. These shift registers can switch 24V and have 8 channels each, so you would need 9 of them.

Please explain how you think you can run these leds without using mains power and why you think that will be more stable.

6

From what I can gather the OP only has an led strip with two wires and he only wants to switch relays to control whole strips on and off. He has 70 such strips and so needs 70 relays and so the need for 70 Arduino outputs.

7

I agree, Mike. But if the store are not too long, the OP could replace 70 relays with 9 high current shift registers which would be much less bulky, more reliable and quieter.