I'm a bit of a noob when it comes to electronics so looking for some advice on this project I have in mind.
The goal is to have my garage door opener (GDO) switch a secondary set of 12v or 24v lights on and off.
The GDO has it's own LED lights and I've measured the output (using my inexpensive multimeter) to be 18.4V. The LED lights dim then switch off after a period of time so I'm assuming it's using PWM.
The GDO also has a 24V 55mA output for accessories.
I don't yet have a specific secondary light I will use but one that I have in mind is rated at 24V 1W.
I'm thinking of using the IRF540N MOSFET to switch the secondary light on and off with the advantage of also having the PWM of the source dim them.
I'm thinking I could simply wire the Gate of the MOSFET into the LED source. I would then wire the Drain to the negative terminal of the secondary light and wire the Source to the ground of the LEDs and ground of the 24v source (which is probably common ground but I should probably check first).
My main concern is that I don't know if the MOSFET will over load the LED power source. I really can't mess around too much because it's an expensive door opener :)
Since my original plan could possibly damage my GDO if I'm not careful my other plan is to use an LDR circuit to switch the 24+ on and off without the fancy PWM.