In this video I highlight how a bipolar junction PNP transistor operates when being used as a switch. This video demonstrates a simple and practical look that will help you understand what a PNP (Sourcing) transistor does and how it energizes a load.
Industrial electricians are dealing constantly with proximity switches that are configured as either PNP or NPN, this will also help explain which one you will need. PNP Transistors "Source" positive voltage to a load, or a PLC input. They pair with a "Sinking" or NPN PLC input card.
If an electronic assembly or system is noted as configured for PNP, its outputs source positive voltage, and inputs expect positive voltage to energize them.
30 авг 2019