Skip to main content

Why does SMPS Need isolation? – Switch Mode Power Supply

 Switch Mode Power Supply (SMPS) works by converting high AC voltage into DC power using a transformer, rectifier, MOSFET transistor, as seen on Linear Power Supply (LPS).

In essence, it is ideal for providing an additional layer of protection through isolation devices to be included in SMPS.

Isolators are devices used to isolate a particular circuit or equipment from a known power source. It serves as a mechanical switch that allows manipulation of both input and output power sources coming in from an open position and isolates both circuits.

Switch Mode Power Supply


In equipment component failure, isolation serves as a physical barrier to potentially dangerous voltages. By using isolation mechanisms, electric shock and fire hazards are prevented.  


An isolated power supply creates a power output that is electrically independent of its input power. When multiple isolated power outputs are used, the output voltage generated is then independent of one another with relatively no connection in between. Several reasons why switch mode power supply needs isolation include:


Safety Promotion

User safety and device efficiency are fundamental considerations in selecting power supply outputs. Power supplies that have isolation properties are needed in AC supply voltage conversion.


Isolation prevents the main AC voltage from crossing the output gradient, thus preventing equipment malfunction. SMPS uses optoisolators to measure the output voltage created to regulate the power output and further promote system safety.


Also, isolation separates potentially dangerous voltages flowing in from converters powered by high voltages coming from AC mains acting as its primary input, thus promoting user and equipment safety. 


Prevention of Ground Loops

Isolated power supplies prevent the occurrence of ground loops. Ground loops occur when multiple circuits share a single return path.

The current flowing from this ground loop can cause one or multiple courses to malfunction, causing a break in the system. It results in signal noise, communication errors, and damage to the flow of ground current and long cables.


Isolated power supplies help prevent loops from occurring and maintain system integrity even with multiple circuits present.


Equipment protection

SMPS with isolation helps protect equipment from power conduction line-level events such as lightning strikes, electric surges, etc.


Proper insulation of electric pathways is also used to safeguard electrical circuits further. 


Flexibility and Efficiency

System flexibility occurs when power supplies come with multiple isolated outputs.


These allow isolated power supplies to be easily connected to create a higher power voltage or be placed in parallel arrangement to yield higher output currents.


This is also termed voltage level shifting.


Key Takeaways

SMPS converts high voltage AC input to DC output without using a transformer. It utilizes MOSFET transistors and other electrical components during AC/DC conversion.


The use of isolation is a measure that safeguards the equipment from potential electric surges. It also promotes user safety by eliminating electric shocks during breaks in the component integrity.


Isolation removes ground loops from occurring which reduces equipment functionality and efficiency.


Comments

Popular posts from this blog

PLC Program for Mixing Tank

 Create a ladder diagram for controlling a batch mixing process. Implement a PLC program for mixing tank or Mixing Process using PLC Ladder Logic. PLC Program for Mixing Tank Fig : Mixing tank A tank is used to mix two liquids. The required control circuit operates as follows: A. When the START button is pressed, solenoids A and B energize. This permits the two liquids to begin filling the tank. B. When the tank is filled, the float switch trips. This de-energizes solenoids A and B and starts the motor used to mix the liquids together. C. The motor is permitted to run for 1 minute. After 1 minute has elapsed, the motor turns off and solenoid C energizes to drain the tank. D. When the tank is empty, the float switch de- energizes solenoid C. E. A STOP button can be used to stop the process at any point. F. If the motor becomes overloaded, the action of the entire circuit will stop. G. Once the circuit has been energized, it will continue to operate until it is manually stopped. Solution...

What is Relay? How it Works? Types, Applications, Testing

 We use relays for a wide range of applications such as home automation, cars and bikes (automobiles), industrial applications, DIY Projects, test and measurement equipment, and many more. But what is Relay? How a Relay Works? What are the Applications of Relays? Let us explore more about relays in this guide. What is a Relay? A Relay is a simple electromechanical switch. While we use normal switches to close or open a circuit manually, a Relay is also a switch that connects or disconnects two circuits. But instead of a manual operation, a relay uses an electrical signal to control an electromagnet, which in turn connects or disconnects another circuit. Relays can be of different types like electromechanical, solid state. Electromechanical relays are frequently used. Let us see the internal parts of this relay before knowing about it working. Although many different types of relay were present, their working is same. Every electromechanical relay consists of an consists of an Elect...

Ferrules and Cross Ferruling

 Ferrules are identification labels provided for every wire terminations in an instrument, equipment, or electrical/instrumentation control panels. These tube-shaped sleeves can be inserted easily on each individual wire in a multi-core cable. In earlier days fixed digits/letters are used as ferrules, but now Instrumentation engineers/technicians prints out desired ferrules by using a ferrule printing machine. Typical Ferrule The numbers/ letters on the ferrules will be given as per the approved electrical hook up or loop diagrams. This helps technicians to easily identify a particular loop/wiring from a series of terminal blocks and to troubleshoot the desired terminal connection. Separate numbers on the ferrules distinguish the positive and negative polarities of wires, thus ensure the polarity protection of the instrument. Cross Ferruling  As a wire is connected on its both ends, it is quite useful to use a cross reference method for wire identification. Unlike normal ferru...