What is Galvanic Isolation : Working & Its Applications

Isolation technique is used while designing an electronic product that uses more operating voltages and signals to avoid one signal that is messing up with the other. Isolation plays a key role in security by avoiding the fault conditions of grade products in industries. Generally, isolation is also known as galvanic isolation. As the name suggests, galvanic signifies the flow of current generated through some kind of chemical act & when we are isolating the current through breaking the contact of a conductor is known as Galvanic Isolation.

What is Galvanic Isolation?

Definition: Galvanic isolation is used to divide the input & output supplies of a device to allow the flow of current through a field or through electrical connections. It allows the transfer of power among two circuits that should not be coupled. The main reason to create isolation is security from fault situations within industrial-grade products & where the wired communication is required among two devices however every device controls its own power.

Galvanic Isolation
Galvanic Isolation

This is used in electronic equipment to handle distortions without any trouble. In this method, an ultimate earth fault can be observed & rectified before it approaches a malfunction of the system. This kind of isolation can diminish safety risks while working on the systems.

How Galvanic Isolation Works?

Galvanic isolation separates two electrical circuits where there is no flow of electrons. This isolation can perform the physical partition between the input & output. By adding this isolation among two systems, it can remove all the surge & grounding problems. Before adding isolation, the two systems will share two grounds through the threat of current flow among them however from this, we have two completely closed ground systems excluding current flow among them. This isolation smashes the ground lane with the help of air gaps, optical devices otherwise transformers. This isolation permits the flow of data between two systems however not electrical current.

Types of Galvanic Isolation

There are different types of isolation techniques and selecting the correct technique mainly depends on the isolation type, withstand capacity, application necessities & the cost factor.

Methods for Signal Isolation

The methods of signal isolation include optoisolators and Hall Effect sensor



An optoisolator is used whenever a signal is compulsory to pass among two ground potentials, This is a photoresponsive transistor used to activate once it’s internal light-emitting diode is activated. The light generated from this diode is the signal lane & it does not break the isolation wall among ground potentials.

Hall Effect Sensor

Hall effect sensors permit an inductor to transmit information across a little gap magnetically. Not like to optoisolators, they do not include a source of light through a fixed life & compare with the transformer-based approach they don’t need DC balancing.

Methods for Power Isolation

The methods of power isolation include transformer and capacitors


Galvanic Isolation in the Transformer is the most frequently used isolation type. There are huge applications of the transformers where the most frequently used one is to step up and step down the voltage. In the transformer, it does not have any connections among the two windings namely primary & secondary however it can step down the voltage from high AC to low AC voltage with no loss of the galvanic isolation.


The main function of the capacitor is to allow alternating current to flow and blocks direct current. These components connect ac signals at different voltages between two circuits. Based on the conditions, it may get damaged by getting short-circuited. The main purpose of producing this isolation is to prevent the event of a malfunction from a current source.

Galvanic Isolation in UPS

Some uninterruptible power supplies offer galvanic isolation but most of the online units don’t provide this isolation. For instance, Unison, Exide is online models so they don’t offer this isolation whereas the standby ON sequence by “Oneac” will offer this isolation. So, isolation is not a kind of UPS function, but quite a characteristic that can be given to any UPS.

Galvanic Isolation Vs Electrical Isolation

The difference between galvanic isolation and electrical isolation includes the following.

Galvanic Isolation

Electrical Isolation

This type of isolation separates two electrical circuits for eliminating stray currents Electrical isolation is a technique used to control corrosion
This is used wherever two otherwise more circuits have to commune, however, their ground terminals may be at dissimilar potentials This isolation prevents the flow of hazardous voltages when a fault occurs otherwise component malfunction & stops the damage.
This is used in Power generators, Motor controllers, Distribution systems, measurement systems, I/O logic devices, etc. This is used in welders because there is an opportunity of getting a shock through touching lead or hot component within the welder.


The applications of galvanic isolation include the following.

  • Galvanic isolation is an extremely important parameter and the application of this is enormous. It is used in industrial, consumer goods, medical, and in the communication sector.
  • In electronic industries, this kind of isolation is used for power generators, measurement systems, distribution systems, I/O logic devices & Motor controllers.
  • In the medical field, this is one of the main priorities used in the medical equipment which can be connected directly through the bodies of patients like Defibrillators, Endoscopes, ECG & different types of imagining devices.
  • These are used in communication systems at the consumer level. The examples are routers, Ethernet, switches, and many more. Standard consumer goods such as SMPS, chargers, logic boards of computer are the most frequently used devices which employ galvanic isolation.


1). What is isolation?

Isolation is used to stop the damage to the electrical circuit when it is under fault conditions.

2). What are the types of galvanic isolation?

They are signal, power level and capacitors like an isolator

3). What is the function of signal isolation?

It is used where the two different natures of circuits are conversing with each other with some kind of signal.

4). What is the function of power level isolation?

These types of isolations are necessary to separate low power devices from high power loud lines.

5). What are the practical examples of galvanic isolation?

They are IC MAX14852 or MAX14854

Thus, this is all about an overview of galvanic isolation, types with their applications. Here is a question for you, what is the galvanic isolation in PLC?