> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt # Mini Basic PIR Sensor - BL412 **Type:** Product page · **SKU:** ADA4667 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia) **Page:** https://core-electronics.com.au/mini-basic-pir-sensor-bl412.html ([markdown](https://core-electronics.com.au/mini-basic-pir-sensor-bl412.html.md)) PIR sensors are used to detect motion from pets/humanoids from about 5 meters away (possibly works on zombies, not guaranteed). This sensor is much smaller than most PIR modules, which makes it great for unobtrusive projects. It's also fully-contained - only needs power, ground and a resistor to set the delay time - and breadboard or perfboard friendly. ## Pricing - **Price:** $3.90 (inc GST) — $3.55 AUD, exc GST - **Quantity discounts:** 10+ $3.44 (exc GST) · 50+ $3.36 (exc GST) ## Availability & dispatch - Out of stock — the product page offers email notification when it returns. ## How to buy - **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=ADA4667:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart. - **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/ADA4667:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.) - **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there. - **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works) - **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt ## Description PIR sensors are used to detect motion from pets/humanoids from about 5 meters away (possibly works on zombies, not guaranteed). This sensor is much smaller than most PIR modules, which makes it great for unobtrusive projects. It's also fully-contained - only needs power, ground and a resistor to set the delay time - and breadboard or perfboard friendly. Runs on 3.3V power - so make sure if you're interfacing with an Arduino or other 5V chip, you power it from the 3V regulator. Digital signal output is 3.3V high/low and you can change the length of time the signal pin stays high by connecting a resistor divider to the second pin, from 2 seconds (0V) up to one hour (3.3V) - see the datasheet 'on time' table for recommended resistor values. To use, see datasheet page 7 pin-out diagram: - Connect pin #1 to ground - Connect pin #2 to ground (on time of 2 seconds) - Connect pin #3 to 3.3V - Check signal on pin #4 The snap-on lens is focused to 5 meters away with a 120 degree spread, but should work from about 3 to 8 meters. [These are smaller and less expensive than Adafruit's PIR modules, and you'll find the performance is OK but not as great as the larger modules, for example not having as wide of a range and taking longer to trigger.](https://core-electronics.com.au/pir-motion-sensor.html) [For a PIR tutorial with CircuitPython and Arduino code examples and project ideas, check out Adafruit's ](https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor)PIR sensor tutorial page[!](https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor) The BL sensor window is 5mm x 3.8mm. We also carry the [BS412 PIR sensor](https://core-electronics.com.au/mini-basic-pir-sensor-bs412.html) which has a smaller sensing element. Specifications - **Note: PIR sensors and the Raspberry Pi sometimes don't get along - if you're having false trigger reports, make sure the PIR Sensor is far away from the Pi** - [Specification Sheet](https://core-electronics.com.au/attachments/localcontent/4667_C15116_19844eda999.pdf) - [Lens Diagram](https://core-electronics.com.au/attachments/localcontent/4667_lensdiagram_34100be8031.png) ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/4/6/4667-06.jpg)