What is Manual Transfer Switch : Working & Its Applications

We know that a transfer switch is used to shift the electrical load between two power sources. These switches are operated manually or automatically so they can be called manual or automatic transfer switches. The manual transfer switch (MTS) operates by the operator to transfer the load to the generator whereas the automatic manual transfer switch (ATS) operates automatically to move the power from one power source to another when there is a power outage. An ATS is applicable for large properties whereas an MTS is applicable for small homes. This article discusses an overview of a manual transfer switch – working with applications.

What is a Manual Transfer Switch?

A manual transfer switch definition is; a switch that operates manually to shift the power from one power source like mains to another power source like a generator when a power failure occurs. This switch requires an operator to rotate an alternative lever or handle to switch in between the mains power source & the generator to start the generator manually.

How Does a Manual Transfer Switch Work?

A manual transfer switch simply connects the electrical circuits of houses to the generator. When a power failure occurs, the operator switches on the backup power source so that any load connected to the circuit will turn ON through backup power. This switch is simply used indoors & outdoors. So based on the output of a generator, the number of circuits can be connected manually.

Manual Transfer Switch
Manual Transfer Switch

Where to Use Manual Transfer Switch/ Circuit Diagram of Manual Transfer Switch

A manual transfer switch is a switching device, used to exchange the power supply source for an electrical load. These switches are available with handles & metallic paths where these paths are connected in such a way that they will connect to each other once we change the handle position of the switch manually. The connection of this automatic transfer switch is shown below.

Manual Transfer Switch Circuit Diagram
Manual Transfer Switch Circuit Diagram

Here in the above circuit diagram, we can observe that the switch includes completely eight terminals where 4 terminals are arranged on the upside and 4 terminals are arranged on the downside. So these terminals must be connected in parallel. Also, grounding or electrical earthing is given to this switch for electrical safety.

This switch connection will assist you to connect both of the power sources for the house wiring. At the terminal of load, you must connect the main incoming terminal of an entire load of the house. Here, you can connect the o/p of the energy to power source 1 & generator to the power source 2.

In general, two different power sources & one load can be connected to this switch. The operating of this switch is; that once we change the handle position then the load will disconnect from one power source & connect to the remaining power source. Here power sources are the main power source and a backup power source.

The handle of the manual switch can be operated within three positions source 1, 2, & off position. Once the handle of this switch is moved to the off position, the load will be isolated or disconnected from the power source. Once we move the switch handle in power source 1, the load will connect to source 1 & disconnected from power source 2. Alternatively, whenever we move the switch handle to the source-2 position, the load will be connected to power source 2 & disconnected from power source 1.

Manual Transfer Switch Vs Automatic Transfer Switch

The difference between a manual transfer switch and an automatic transfer switch includes the following.

Manual Transfer Switch

Automatic Transfer Switch

Manual transfer switches are very reasonable & simplistic. Automatic transfer switches are expensive.
These switches operate manually, so an operator is required to operate this switch. These switches operate automatically.
A manual switch is not used with a generator permanently. This switch is used with an electric generator permanently, so when a power outage occurs then the generator will give an emergency backup supply to your building.
In this switch, every time power flow needs to be changed manually. In this switch, there is no need to change the power flow manually because it is automatic.
This switch requires technical skills to operate. This switch doesn’t require technical skills.
It requires more work while operating. It doesn’t require more work.

How to Select a Manual Transfer Switch?

A manual transfer switch (MTS) is a lifesaver whenever you require a safe and very fast electrical power supply. So selecting the proper size manual transfer switch is a struggle, particularly if you are unconfident how much capacity of supply your building requires.

There are many benefits of using these switches; it improves safety, hardwired appliances can be easily powered like the A/C, and connectivity to the whole service panel.

The generator should not plug directly into an outlet in your home which is called backfeeding, as it can cause an electric shock to someone & can cause a fire accident in your home. So, proper installation of these switches can eliminate these risks.

The selection of a manual transfer switch mainly depends on different parameters like amps, circuitry, wattage, etc which are discussed below.

Choosing Amps

The usage of this switch mainly depends on the size of a generator as well as your property so a smaller or larger manual transfer switch is used. The larger switch uses more amps whereas the smaller switch uses fewer amps. For instance, if you have a large company including a large store with multiple systems, then you use a larger generator so it needs a larger manual transfer switch.

Choosing Circuitry

Some owners of businesses may decide to power more circuits as compared to their opponents throughout a blackout. No matter the reason for your power outage otherwise how long it lasts, but you will need to power different systems that are critical to your everyday operations. So manual transfer switches handle any amount of dedicated circuitry.

Choosing Wattage

The amount of wattage necessary to securely function your generator mainly depends on the building’s electrical capacity & the number of various circuits you wish to run. If you need to control more circuits, then maximum wattage is required.

Wattage Meters

There are many manual transfer switches available with in-built wattage meters that keep track of what is being powered. So, without wattage meters, the system can be overloaded and appliances & generators can be damaged.

Pros and Cons

The pros of a manual transfer switch include the following,

  • These switches are not expensive to design and install.
  • The size of these transfer switches is small.
  • It doesn’t require any control cables.
  • This switch has high short-circuit withstand capability
  • Quick-make and brake operation.
  • Rugged design.
  • It works in compact environmental circumstances

The cons of manual transfer switch include the following,

  • These switches are prohibited where it is needed to quickly switch power sources whether a person is available or not.
  • These transfer switches operate manually.
  • Every time generator needs to be started manually.
  • It takes much time to connect your temporary electrical power supply as compared to an automatic transfer switch.


The applications of manual transfer switch include the following.

  • These switches help in maintaining the lights & other essential systems powered when an emergency or temporary power outage occurs.
  • These types of transfer switches are used in buildings, industries like manufacturing, automobile, etc.
  • This switch allows the operator to enable a generator & restore the power supply to fixed circuits once the utility power supply fails.

Thus, this is all about an overview of a manual transfer switch – working with applications. These switches transfer the power supply from one power source to another power source manually. These types of transfer switches are typically used for low power & home-usage. Usually, these switches handle current supply in the 16 to 120 A range. Here is a question for you, what is an automatic transfer switch?