Intelligent PIR Infrared Motion Sensor Module - White (DC 5~24V)

Pros: + quite accurate inner timer + plastic cover + long enough connector cables + cables are connected by commonly used connector

Cons: - not very sensitive, but is able to detect general movement - capacitors and transistor on the back side are quite large - one plastic cover of the two I ordered is not holding really well, the other one is fine

Other: Worth for things like automatic lights in not really frequent hall or so, but if you require more sensitivity, rather look for something else.

Pros: Relatively cheap. You can get a cheaper version without the leads (sku: 139624). This version just makes it easier to prototype with as you can just stick the leads into your breadboard. It's very easy to use and quite self-explanatory. Which is good, because it comes with zero documentation :) Red lead goes to 5V, Black lead is GND and the Yellow lead is your output. (In arduino, the input will be HIGH on movement detection)

Cons: It's rather large. Makes integrating with smaller projects (which is what I'm working on!) harder. Range is not nearly as far as it says (it says 7-20 metres!). In reality its more like 2-3 feet away. Looks like the one from the above sku I posted has a couple of adjustment screws which can adjust sensitivity and HIGH edge times.

Other: I'd recommend it if you just need something for quick prototyping.

Pros: a well price and reliable unit. has good sensitivity. Works well with 5- 15 V input range. made a couple of switches battery powered one and 12 volt adapter powered with the units and all works well.

Cons: size is a bit to bulky for fitting / making a compact switch, but manageable. Range is bit less 4-5 M

Other: will not hesitate to buy more units for my needs and i am planning to.