Features of Asco Transfer Switches

Transfer Switches

A transfer switch is a type of electrical switch that transfers a load between two different sources. In a power outage, the utility input is cut from the circuit breaker and reestablished with the generator. The switches do not allow both sources to be connected at one time. Transfer switches are important for companies and homeowners alike.

In the event of a power outage, the transfer switch provides temporary power through your generator. Once power is restored, you can cut the connection from the generator and switch it back to the utility.

While transfer switches offer convenience for homeowners and companies during a power outage, they are also important for utility workers. In the event of a power outage, if you do not cut ties to the utility source before starting the connection to your generator, you can endanger the lives of the linemen. The linemen may find that the powerline they need to work on is “live,” and you risk electrocuting them.

Manual Transfer Switch

manual transfer switch is installed behind the panel of your main breaker. The circuits you would like powered during an outage are connected, and the connection runs outside to the generator. In the event of a power outage, the operator must first cut the power from the utility service manually and shut off individual, non-essential breakers.

Most generators cannot handle the load of running an entire house and, if this is attempted, you could end up overloading the generator. Then the homeowner must start up the generator and allow it to warm up. Once it has stabilized, you can switch the power to the generator.

Automatic Transfer Switches

Automatic Transfer Switches, simply referred to as ATS, are installed with a backup generator. An ATS provides temporary power if the source of the utility fails. When an outage occurs, the ATS instructs the generator to start. Once the generator is running and can provide power, the ATS cuts power to the utility line and reroutes to the generator.

After a delay, the generator runs the selected switches and temporary power is restored. Conveniently, when the power returns, the ATS instructs the generator to switch off, cuts the connection, and reestablishes a connection with the utility line. There is a brief cool-down period during the switch.

Manual transfer switches are generally used for a freestanding generator while automatic transfer switches are employed with a built-in automatic generator.

Asco Transfer Switches

Asco Transfer Switches are used in more emergency backup systems than any other switches worldwide. They are behind much of the technological advances in the industry and hold more patents on transfer switches than any other company. Because Asco has set the standards for the industry, their transfer switches offer many in-demand and convenient features.

Asco has both manual and automatic transfer switches, depending on what kind of generator you use and how it has been installed. The transfer switches come in an array of different sizes, capabilities, and load sizes. There are four different series available, all with different capabilities and purposes. You can determine what kind of transfer switch by looking at the type of generator you have.

185 Series


  • Handles up to 400A load sizes
  • Available in automatic and manual
  • Single phase
  • Double throw contacts-prevents system from being connected to generator and utility source at the same time

300 Series


  • Telecom, agriculture, commercial, light industrial, and municipal applications
  • Offered in both manual and automatic
  • Handles load sizes up to 3,000A
  • Double throw contacts
  • Single or three phase

4000 Series


  • Designed for protecting healthcare facilities, data centers, manufacturing/fabrication plants
  • Handles loads up to 4,000A
  • Single or three phase
  • Double-throw contacts
  • Both manual and automatic operation

7000 Series


  • Critical loads like healthcare facilities, manufacturing, mission critical applications, industrial, and emergency services
  • Loads up to 4,000A
  • Single or three phase
  • Double throw contacts
  • Bypass isolation switches

Some of the most notable features on the Asco Transfer Switches are the automatic double-throw features. Accessories have also been designed for these switches, such as heaters for environments that can be extremely cold, extended time delays, and extensive surge protection.

The microprocessor and LED display on the front access panel gives users an easy rundown of their immediate situation and current utility and unit power status. The units offer solid, switched, or overlapping neutral conductors.

Final Thoughts

Asco Transfer Switches have been designed for a wide array of applications, homes, businesses, and public services. Asco transfer switches are easy to install in homes, small businesses, and industry applications alike. The company invented the ATS and has 110 years of experience. When dealing with something as important as a throw switch, it is important that you get the most reliable ones in service.