question about PIR

[Guest firefli]

I Have a LED light with a motion sensor and photo sensor.
I would like to eliminate the motion part so the light is on all the time when it gets dark.
the QUESTION is would putting a jumper across the source and drain or the source and gate
of the PIR turn it on all the time.

Any advice would be appreciated, Thanx

[audioguru]

A PIR probably does not have Mosfet pins. Most have an ordinary little transistor at the output that drives an external relay, power transistor or power Mosfet.
If you put a jumper across its two output pins then it will probably stay turned on.

[Guest firefli]

Thanx for your advice.
I have attached 2 pics. of the PIR's showing the 3 pins.
Are the output's the pins marked in yellow????
thanx again

[audioguru]

Whatever you have does not look like a PIR motion detector because it does not have a Fresnel lens.
It is anybody's guess what its 3 pins are for. It doesn't even have a manufacturer's logo or a part number printed on it for you to look at its datasheet.

[Guest firefli]

I removed the lens when I opened the case.
I assume the unit was made in china which is why there are no markings. But I will look closer with a magnifyer.
The 2 cylinders with the rectangle windows in the pic. look just like the PIR's I saw on google images.
I'm like 95% sure thats what they are.

[audioguru]

You could measure the one you have to find the positive supply pin, the 0V ground pin and the output pin. Then if you short the output it might become destroyed.

[pebe]

It may be one of these.

http://www.bitsbox.co.uk/data/es0550.pdf

[audioguru]

If it is then shorting D to S will keep it always turned on, but not cause the circuit to think there is always motion which needs an AC signal created by the Fresnel lens. The circuit will simply do whatever it does when the FIR is exposed to continuous IR light.

I am surprised to see that it has a tiny solar panel inside that develops a voltage when exposed to IR light. Then the voltage turns on the Mosfet.