A comprehensive guide to changeover switches

An electrical switch that allows switching of load from one electrical source to another and vice versa is called a changeover switch. Changeover switches can be either manual or automatic. For example, in case of power failures, a generator changeover switch is used for quickly switching from grid power to generator power. Therefore, changeover switches are also known as transfer switches.

Transfer switches are also effective in isolating power sources when not in use. From simple home use to commercial and industrial use, changeover switches have found a wide variety of uses. You can see uses of changeover switch in,

• Homes with small power generators
• Small business establishments
• Schools and educational institutions
• Malls and other commercial establishments
• Hospitals, clinics, and healthcare institutions
• Factories, warehouses, and industrial complexes
• Telecommunication and data network towers

How does a changeover switch work?

In simple terms, a changeover switch works as a bridge that connects two electrical sources. When activated, the switch will shift the flow of current from the main source to an alternate source and vice versa. The flow of power is usually transferred when the main power source fails to provide enough electrical power.

The changeover or transfer of power is done manually or automatically, depending on the type of switch in use. There are three main types of changeover switches:

1. Manual changeover switches: As expected, a manual changeover switch requires someone to go flip the switch when power failure occurs. It is a simple operation that requires no technical expertise. And once the main power source is back online, a reverse flip of the switch needs to be done to revert to the primary power source.
2. Automatic changeover switches: These transfer switches can detect faults in the main power source and automatically switch to an auxiliary power source. When the power is restored to the main source, the automatic changeover switch reverts to the primary source on its own.
3. Hybrid changeover switches: These switches offer a versatile mode of operation for Photovoltaic (PV) or solar systems. When the energy from solar is not enough to power the load, a hybrid changeover switch can function in grid-tied mode until power is restored.

Rated operational current of changeover switches

A rated operational current of an electrical accessory is designated by the manufacturers, taking into account its operational voltage, frequency, duty and utilization category, along with protective enclosures, where needed.

For example, Lauritz Knudsen (Formerly L&T Switchgear) changeover switches are rated using amperage. Rated current amps of the Lauritz Knudsen (Formerly L&T Switchgear) changeover switches are between 63 to 2000 amps. Which makes Lauritz Knudsen (Formerly L&T Switchgear) changeover switches a great choice for diverse use cases. For more details, you can check out C-Line Enclosed Automatic Transfer Switches and C-Line Manual Changeover Switches. 

Also Read:

• What Is A Contactor? Types, Use, And Applications
• What Is A Changeover Switch And Its Function?

Benefits of using changeover switches

The importance of changeover switches as an electrical component is undeniable for establishments that need continuous power. Here are the main benefits of using changeover switches:

1. Reliable power supply: A good changeover switch allows you to seamlessly switch between grid and backup power, ensuring continuous operation even during power failure and voltage fluctuations.
2. Increased safety: Changeover switches are also critical for the safety of people, personnel, and equipment in establishments where continuous power supply is a must have. For example, heavy industrial settings, hospitals, etc.
3. Non-technical operation: Changeover switches are simple switches which are easy-to-install and operate. Thus, allowing you to have uninterrupted power supply without the hassle of training staff and spending money on maintenance.
4. Durable by design: Changeover switches made by reputed brands, such as Lauritz Knudsen (Formerly L&T Switchgear) changeover switches are durable and can be customized to fit different requirements. Made from high-quality materials, these switches are wear and tear resistant, avoid corrosion and damage by UV radiation.
5. Covered by warranty: Reputable changeover switch brands also offer warranty cover on their products, which make repair and replacements hassle-free just in case there is a problem with the product.

Wiring a changeover switch for your home or business  

Here are the installation steps to follow:

1. Disconnect the power supply.
2. Identify the circuits that need to be powered after the changeover.
3. Match the circuit inlets with the circuits that need power.
4. Remove the knockout from the service panel to balance the load inside the transfer switch.
5. Connect the wires from the transfer switch into the knockout hole. The wires are labeled to show the circuit they feed inside the switch box.
6. Take care not to damage the insulation.
7. Attach the conduit from the switch box to the main panel.
8. Mount the transfer switch near the service panel ensuring a minimum distance of at least 45 cm from the main panel.
9. Disconnect the hot wire lead from the breaker and connect the red wire to the breaker.
10. Reinstall the breaker.
11. Connect the black wire to the old feed wire. The black wire should be coming from an identical changeover switch circuit.
12. Complete the process for all circuits.
13. Connect the read leads to the double pole breaker.
14. Connect the neutral white wire from the changeover switch to the neutral bus bar.
15. Attach the green wire from the switch to the open port found on the grounding bar of the service pane.
16. You are done.

While these steps provide a cursory overview for installation of changeover switches, the installation itself should be done by a trained and certified electrician.

Maintenance tips for changeover switches  

Like all electrical components, changeover switches also require regular upkeep for safe and long lasting operation. Primarily, you can perform a visual inspection of the changeover switch to identify any degradation or warning signs. Post that, maintenance of a changeover switch needs to be handled with care. Here are some tips to do that safely,

1. De-energise the changeover switch before cleaning.
2. Do not use blowers and vacuum cleaners to clear dust and debris around the switch.
3. Use a brush with soft bristles and a dry cloth to clean grime and moisture from the switch.
4. If needed, apply lubrication on the parts that carry current.
5. Remove the arc chutes / transfer switch barriers to clean the contacts within.
6. Clean the contacts with a dry non-abrasive cloth.

Please note that these actions are for informational purposes and in real life, maintenance of changeover switches should be performed by a certified technician only.

Selecting the right changeover switch for your use  

A changeover switch is unlike a regular switch or socket that you can pick and choose to install. Selecting the right changeover switch requires technical knowledge and skill. So, refer to your electrician's advice for selecting and buying the right switch for your home or business.

However, once you know the type and technical specification of the transfer switch you will need, you can refer to the Lauritz Knudsen (Formerly L&T Switchgear) for checking out changeover switch prices online. We offer a one-stop solution for retail and bulk purchase of Lauritz Knudsen (Formerly L&T Switchgear) electrical products online in India.

That's all for our comprehensive guide on changeover switches, for more information, you can contact us anytime.