---
title: openSensor
description: "**What is openSensor used for?** openSensor is used to detect when doors, windows, gates and other moving parts are opened and closed. Information about changes in status can be used for monitoring and automation. **How do you power openSensor?** openSensor…"
url: "https://faq.blebox.eu/en/docs/opensensor/"
updated: "2026-09-25"
category: "Wi-Fi controllers"
---

# openSensor

**What is openSensor used for?**
openSensor is used to detect when doors, windows, gates and other moving parts are opened and closed. Information about changes in status can be used for monitoring and automation.

**How do you power openSensor?**
openSensor should be powered by 5–48 V DC. Connect the brown wire to the positive (+) terminal and the green wire to the negative (GND) terminal.

**How does openSensor detect a change in state?**
openSensor detects a change in state using a magnet or a dedicated twinMagnet. Bringing the magnet closer to or moving it away from the sensor causes a change in its state, which allows it to detect the opening and closing of doors, windows, gates and other moving parts.

**What is twinMagnet?**
TwinMagnet is a dedicated accessory designed to work with the openSensor. It simplifies installation and ensures correct status detection. Alternatively, you can use a different magnet instead of the twinMagnet, provided its strength and method of attachment allow the sensor to function correctly.

**How do the openSensor outputs work?**
The openSensor has two open-collector outputs, which are shorted to earth (GND). One output indicates an open state, and the other a closed state. The maximum load current for each output is 50 mA.

**How many states does openSensor distinguish?**
openSensor distinguishes between two or three states, depending on the settings and the magnet used. With a single magnet, the open and closed states are detected. When using a twinMagnet, which consists of two magnets, it is possible to detect three window states:
Open – neither magnet is detected by the sensor;
Tilted – only one magnet is detected;
Closed – both magnets are detected.