Electrolytic Capacitor in Solenoid Circuit

Thread Starter

Sim City

Joined May 21, 2019
It storages energy and release it when the solenoid is active to avoid that voltage drop ?


Joined Mar 10, 2018
If the 12V power supply is "stiff", say a 12V battery gel cell, located
with short low ohm leads to the load and rest of circuit, or the 12V source
has its own internal capacitive filtering, again close to load and rest of circuit,
I would say its not needed.

The Cap typically ESR is ~ 200 mOhms, the Gel Cell ~ 50 mOhms depending
on size. Of course this depends on battery capacity and chemistry.......

However if 12 V a wall wart with long power lead, for example, the cap very much

If you have a scope, use in one shot mode and trigger so that it captures transient,
with and without cap. Then decide.

if you use cap pay attention to its datasheet ESR, one vendor to another all over the
map in performance.

Regards, Dana.
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