First of all, let us understand what is a NPN sensor.


NPN Sensor - The full form of NPN is Negative-Positive-Negative. In the NPN sensor, the output is always negative. We know that the proximity sensor is in two wires, three wires, four wires and five wires.


Now we understand how to connection of NPN sensor. Two wires, three wires, four wires and five wires, any type of NPN sensor all have the same connection.

Let us understand this by the circuit diagram given below.



Understand that, we have three wire NPN sensors. So we will do its connection with PLC in this way. in Three wire sensors, have brown, blue, and, black colored wire. In brown we will connect + 24V, in blue we will connected 0V and black wire will be connected to the PLC input.


Now one thing will always be kept in mind here. If we are connecting NPN sensor, we will always give +24V at common point of PLC. Because the black wire of the NPN sensor that we are getting output is negative.


We make the same connection for PNP sensors as well. The only difference is that we give 0V at the common point of the PLC. Because we are getting the output from the black wire of the PNP sensor which is in the positive.


 

In Hindi


सबसे पहले हम समझते है की NPN सेंसर होता क्या है। 


NPN सेंसर - NPN का फुलफॉर्म, नेगेटिव-पॉजिटिव-नेगेटिव होता है।NPN सेंसर में आउटपुट हमे हमेशा नेगेटिव में मिलता है। हम ये तो जानते है कि प्रोक्सिमिटी सेंसर दो वायर,तीन वायर ,चार वायर और पाँच वायर में होता है। 


अब हम NPN सेंसर का कनेक्शन कैसे करते हैं ये समझ लेते है।दो वायर,तीन वायर,चार वायर और पाँच वायर कोई भी NPN सेंसर हो सभी का कनेक्शन एक ही प्रकार से होता है। 


चलिए इसे नीचे दिये हुये सर्किट डायग्राम के द्वारा समझते है।


समझ लो हमारे पास तीन वायर NPN सेंसर है। तो हम इसका कनेक्शन पीएलसी के साथ कुछ इस तरह से करेंगे। तीन वायर सेंसर में ब्राउन ,ब्लू ,और,ब्लैक रंग का वायर होता है। ब्राउन में हम +24V , ब्लू में में हम 0V और ब्लैक वायर पीएलसी के इनपुट में कनेक्ट हो जायेगा। 


अब यहाँ पर एक बात का हमेशा ध्यान रखियेगा।

 अगर हम NPN सेंसर का कनेक्शन कर रहे है तो हमेशा पीएलसी के कॉमन पॉइंट पर हम +24V ही देंगे। क्योकि NPN सेंसर के ब्लैक वायर से जो हमें आउटपुट मिल रहा है जो नेगेटिव में होता है। 

 

 ऐसा ही कनेक्शन हम PNP सेंसर के लिए भी करते है। अंतर सिर्फ इतना होता है की पीएलसी के कॉमन पॉइंट पर हम 0V देते है। क्योकि PNP सेंसर के ब्लैक वायर से जो हमें आउटपुट मिल रहा है जो पॉजिटिव में होता है।