DescriptionRound Proximity NPN NO Round Sensor 12*12 For Cnc Router&Square Proximity NPN NO Squire Sensor 18*18 For Cnc RouterNPN (depending on purchase option)- Voltage Range: 6VDC to 30VDC- Detection distance from a conductive material: 4mm- Normally Open type switch: Should be connected in Parallel or on a single inputThe three connections are: Positive, negative (to essentially add current to the device), and the signal out which will connect to the input terminal. The brown wire is the positive wire and should be connected to the positive terminal of a power source. The blue wire is the negative wire and should be wired to the negative terminal of the same power source. The black wire will be connected to the input terminal on the controller or interface or breakout board of the CNC router or other type of machine. Typically, this sensor would use a 24 volt DC power supply that is used with the controller or interface.NPN NO Sensor Limit Switch Proximity Axix Round Squares Cnc RouterNPN NO Sensor Limit Switch Proximity Axix Round Squares Cnc RouterMagnetic Proximity Sensors:Magnetic sensors detect changes in the magnetic field caused by the presence of an object.When an object enters the sensor’s magnetic field, it disrupts the magnetic lines, and the sensor registers the change.Usually, a microcontroller or a specific proximity-detecting integrated circuit (IC) is used to interface with a proximity sensor. The kind of sensor and the desired use will determine the precise implementation. By understanding the sensor data and establishing suitable thresholds, you can initiate actions contingent on the proximity of objects.The inductive proximity sensor will engage (become closed since this switch is normally open) when a material that can conduct electricity (conductive metals) nears the proximity sensor. When the proximity sensor is engaged, the signal (black wire) will go low (0 VDC or GND). The material will determine how near it will be before the switch engages.