We need an SMPS (Switched Mode Power Supply) because almost all industrial automation devices — such as proximity sensors, PLCs, relays, solenoid valves, and controllers — operate on 24V DC, while the main power supply available in factories is 230V AC. The SMPS converts this high AC voltage into a stable 24V DC output safely and efficiently. Without an SMPS, these electronic components cannot function properly or may get damaged due to voltage fluctuations.
Unlike older linear power supplies, an SMPS uses high-frequency switching to convert power efficiently. It offers higher energy efficiency (up to 90%), generates less heat, and is more compact. Because of this, SMPS units are preferred in control panels, PLC cabinets, machine tools, and instrumentation systems, where space and energy savings matter. The high-frequency switching also ensures fast voltage regulation, keeping output stable even when input voltage varies.
Another reason we need an SMPS is for protection and reliability. It includes built-in features such as short-circuit, overload, and over-voltage protection, which safeguard expensive automation components. Since most industrial sensors and controllers require a clean, ripple-free DC voltage, the SMPS ensures smooth operation without signal interference or false triggering.
In simple words, an SMPS is the heart of every industrial control system. It converts 230V AC mains power to 24V DC, ensuring that all sensors, PLCs, and control devices receive a stable and safe supply. It saves power, reduces panel heat, and extends the life of equipment — making it an essential component in modern automation and electrical design.