Re: [CAD_CAM_EDM_DRO] Relay question about diodes across the coil

Paul Davis wrote:

>Diodes are a good idea for DC even if you don't care about the spike caused by the back emf. The relay will remain latched until it dissipates it's magnetic field. Assuming it doesn't destroy your driving electronics or short it's coils it can cause the relay to remain latched for a few seconds after the input is removed. So for the sake of speed it's a good idea to have the diode.
>
>

Huh? With the diode, the field dissipates slowly, but it is usually
done in tens of
milliseconds. Without the diode, the field dissipates VERY rapidly,
unless it
arcs over in the coil, and the field collapses in microseconds. So, the
diode
slows it down, rather than speeding it up.

Jon