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I don't know that much about electronics, but I was able to put together this PIR module:

(original)

and a LED strip and everything works just fine, when the PIR detects motion, it turns the strip on. Then after set time (you can configure that with the buttons on the module, as well as brightness and other things) it turns off..

I would however like to have some sort of manual control over the thing - I just want to turn on the strip manually If I want to, I don't care about manually turning it off - I can do that at the side of power supply/socket. I thought I could just take my multimeter, probe a few points for continuity and finally end up soldering a simple on/off switch between the input and output of +12 rail on the sensor board (the two gold plates).

Would that work? Is there any possibility of damaging the board that way? If I am not mistaken, this should basically simulate two switches in parallel in a circuit right?

I understand that I would lose brightness control I programmed onto the board. Right now when the PIR tells the board to turn on, it only gives about 80% of input voltage on the output and that controls the brightness (I didn't see any flickering on camera, so it should't be PWM, but I could be wrong). Would there be another simple way of soldering a switch that would keep the board programming? Bypassing just the PIR and not the whole board maybe?

Sadly I don't have any schematic for the board.

Thank you very much, sorry for my english, not a native language.

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  • \$\begingroup\$ Schematic is king on this (and most) occasions. \$\endgroup\$ – Andy aka Dec 30 '19 at 13:54
  • \$\begingroup\$ I think you have power on one side and electronic switch on the other side , so bypass the switch in parallel, but keep wire short or say how long .. to see what else must be done. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Dec 30 '19 at 16:19
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schematic

simulate this circuit – Schematic created using CircuitLab

Without reverse-engineering the PIR module, you can't tell if applying +12V to the output when it's supposed to be low will damage it.

One solution would be to use a two-way switch to select either the output of the PIR module, or to override it.

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