2 Wire PIR

I have a 2-wire PIR sensor I would like to wire up to my Ardunio, but dont understand how I transfer power to the PIR and detect movement.

A similar PIR is found at B&Q -> http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=10647512&fh_location=//catalog01/en_GB/categories%3C{9372015}/categories%3C{9372042}/categories%3C{9372188}/specificationsProductType=wired

I am a beginner, used to writing software for a PC, this will be my first project using Arduino so any assistance would be appriciated.

From what I understand (which is based on guess work) the power is transmitted to the PIR and the resitance is measured on its return, does anyone else think this is correct way?

Thank you

Tony Cross

I would not deny that I have tilted at MANY windmills over the years, but for the cost of a traditional PIR, and the simplicity and reliability it would give you, I'd resign myself to "wasting" the 2-wire device, and spend the time on something more fun. I bet you could sell the 2-wire device to someone here, or failing that, eBay.

Speaking of eBay... just received 4 PIR units from China, eBay seller "Good Luck": $18.99 including postage. Came promptly, look fine.

Sorry to be "boring".