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Electronics => Beginners => Topic started by: hyperknot on June 15, 2021, 08:02:14 am

Title: How to wire None - One - Both with Rotary Switch
Post by: hyperknot on June 15, 2021, 08:02:14 am

Hi,

I have a very simple problem. I'd like to make a light with 2 LED strips turn on with 0 - 50% - 100% power. I'd like to do this with a rotary switch.

The 2 strips are independent from each other, but physically are in the same housing so when only one of them is on it looks like 50% power.

I'm puzzled with the rotary switch though. Which type allows me to do this? The ones with the needed current rating on Digikey are the following for 3 positions:
- DP3T
- SP3T
- DPDT

I'm thinking I need a SP3T and solder 2 wires to one output for the 100% setting? Is this the right way to do it?

Title: Re: How to wire None - One - Both with Rotary Switch
Post by: Renate on June 15, 2021, 02:40:20 pm

There's two ways to do this, using a DP3T or a SP3T.
The single pole way needs a diode and obviously only works for DC.

Title: Re: How to wire None - One - Both with Rotary Switch
Post by: Terry Bites on June 15, 2021, 04:45:59 pm

Here. Sorry about the wrong attachment.

Title: Re: How to wire None - One - Both with Rotary Switch
Post by: hyperknot on June 16, 2021, 12:34:18 pm

Thanks a lot, so DP3T is by far the simplest as I see.

Title: Re: How to wire None - One - Both with Rotary Switch
Post by: Renate on June 16, 2021, 12:50:54 pm

Well, you could also just keep the two strings together and wire them to a PWM dimmer.
Twice the light is really only a bit brighter to our eyes
You'd probably want more like 1/4 bright, full bright.