Most CNC'ers run into scenarios where they need to drive relays for their machine control. As the needed coil voltage rises toward 24vdc, you will have to add some simple protection to prevent inductive kickback that can reach the drivers voltage rating and cause failure.

To help ease the pain of doing this without hurting the coil driver, I've been collecting appropriate application notes that should help people in choosing a scheme for their needs. Please feel free to add notes or files here.

If you have ever played with one of those toy( book-like ) shockers from the 70's, you know that a simple pulsed coil( just like a relay coil ) can take a standard AA 1.5v battery and inductively ring to create voltages of 100v or more that give mild shocks. That is what you are trying to tame in your relay.


I think a level shifting folder will follow as I often see this is a related topic that often comes up.

Looking forward to the level shifting folder
Cheers
Bengt

--- In DynoMotion@yahoogroups.com, "studleylee" <indigo_red@...> wrote:
>
> Most CNC'ers run into scenarios where they need to drive relays for their machine control. As the needed coil voltage rises toward 24vdc, you will have to add some simple protection to prevent inductive kickback that can reach the drivers voltage rating and cause failure.
>
> To help ease the pain of doing this without hurting the coil driver, I've been collecting appropriate application notes that should help people in choosing a scheme for their needs. Please feel free to add notes or files here.
>
> If you have ever played with one of those toy( book-like ) shockers from the 70's, you know that a simple pulsed coil( just like a relay coil ) can take a standard AA 1.5v battery and inductively ring to create voltages of 100v or more that give mild shocks. That is what you are trying to tame in your relay.
>
>
> I think a level shifting folder will follow as I often see this is a related topic that often comes up.
>