Proximity sensors are widely used in the industrial field, especially in the automotive field, but there are very many types of sensors, and there are many models, and the quality is also uneven, the following proximity sensors how to wiring:.
1. Proximity sensors have two-wire system and three-wire system of the difference, three-wire proximity sensors are divided into NPN type and PNP type, their wiring is different.
2. Two-wire proximity sensor wiring is relatively simple, the proximity sensor and the load in series to the power supply can be.
3. Three-wire proximity sensor wiring: red wire to the positive side of the power supply; blue wire to the 0V side of the power supply; yellow wire for the signal, should be connected to the load. The other end of the load is connected in this way: for the NPN type proximity sensor, should be connected to the positive side of the power supply; for the PNP type proximity sensor, should be connected to the 0V side of the power supply.
4. The load of the proximity sensor can be a signal lamp, a relay coil or a digital input module of a programmable controller PLC.
5. need to pay special attention to the PLC digital input module to the three-wire proximity sensor type selection. the PLC digital input module can generally be divided into two categories: a class of common input for the power supply 0V, the current from the input module out, at this time, must choose NPN type proximity sensor; the other class of common input for the positive side of the power supply, the current flow into the input module, that is, the trap input, at this time, must be Select PNP type proximity sensor. Do not choose the wrong one.
6. Two-wire proximity sensors subject to the constraints of the working conditions, the switch itself produces a certain voltage drop when on, and a certain residual current flow through the cutoff, the choice should be considered. Three-wire proximity sensor, although an additional line, but not the residual current and other adverse factors, the work is more reliable.
7. Some manufacturers will be close to the sensor "normally open" and "normally closed" signal at the same time, or to increase other functions, such cases, please follow the product specification specific wiring 220v proximity sensor wiring proximity sensor wiring so connected: two-wire proximity sensor Is a rated voltage to set your control voltage, that is, for example, your proximity sensor is 220 volts, then you control the relay's suction coil must be 220 volts, and the control power supply voltage must also be 220 volts. Then use the proximity sensor and the relay coil in series will be fine.