HOW AN AUTOMATIC GENERATOR AND TRANSFER SWITCH SYSTEM WORKS
- The completely automatic transfer switch monitors incoming voltage from the utility line, around the clock.
- When utility power is interrupted, the automatic transfer switch immediately senses the problem and signals the generator to start.
- Once the generator is running at proper speed, the automatic transfer switch safely shuts off the utility line and simultaneously opens the generator power line from the generator.
- Within seconds, your generator system begins supplying electricity to the critical emergency circuits of your home or business. The transfer switch continues to monitor the utility line conditions.
- When the automatic transfer switch senses the utility line voltage has returned at a steady state, it re-transfers the electrical load back to the utility line and resumes monitoring for subsequent utility loss. The generator will continue to run for an engine cool-down period of several minutes while the entire system stands ready for the next power outage.
There are other reasons to uses a transfer switch. You may void your fire or homeowners insurance if you install a generator without a transfer switch, because these switches are required by the building code electrical codes in most areas. The information below explains other information why transfer switches are required. NEVER CONNECT A GENERATOR THROUGH A DRYER PLUG OR OUTLET IN A BUILDING. YOU CAN CAUSE A FIRE OR ELECTROCUTE SOMEONE!
|USE A TRANSFER SWITCH It must be installed by a qualified electrician or knowledgeable person and must comply with all applicable laws and electrical codes. |
Use A Transfer Switch
Use a transfer switch when connecting to a building's electrical system.
Have an Electrician install the isolation switch.
|TRANSFER SWITCH PROTECTS LINEMAN|
The utility line voltage is normally "stepped down" before entering the building, by a transformer. The transformer can work in reverse when voltage is sent through it in the opposite direction and "step up" the voltage. This stepped up voltage, back-feeding through the utility lines, may electrocute workers that come into contact with the utility lines.
A Properly Installed Transfer Switch Protects Linemen
|A TRANSFER SWITCH PROTECTS THE HOME|
Improper connections can allow electrical current from the generator to short circuit with utility line current when power is restored. This can cause a fire in the electrical system.
| Protects The Home or Business |
A Properly Installed Transfer Switch Protects Your Home or Business
|A TRANSFER SWITCH PROTECTS THE GENERATOR|
Improper connections can allow electrical current from the generator to short circuit with utility line current when power is restored. This could cause the generator to explode or burn.
| Protects The Generator |
A Properly Installed Transfer Switch Protects Your Generator
|THERE ARE SEVERAL TYPES|
There are several types of transfer switches that may be used with our generators. We sell both Portable and Small Generator Transfer Switches and Large/Industrial Generator Transfer Switches.
For Portable and Small Generator Transfer Switches
For portable generators and for applications where only part of home or business will have emergency power available; we offer Small Transfer Switches, described below. These switches are limited to 21,000 watts (21 kW) and are usually manually switched.
The information below gives specifications and a just a few recommendations for matching a transfer switch to a generator. All the transfer switches we carry are UL listed and CSA certified. We have detailed descriptions and tables on each type of switch. If you don't find what you need, please ask us. Please go to the Small Transfer Switch page to see the details and the many models we offer. Here is a sample:
|. We Provide Several Types |
4 Circuit, 120V/15A (3-prong)
6 Circuit, 120/240V/20A (4-prong)
6 Circuit, 120/240V/30A (4-prong)
10 Circuit, 120/240V/30A (4-prong)
12 Circuit, 125/250V/50A
(3-pole 4-wire plug)
See our Gen-Tran ordering guide and catalog. Click Small Transfer Switches
|TRANSFER SWITCH OPERATION - |
For Small & Portable Generators
The Transfer switch isolates selected circuits from the home with "Break" then "Make" switches. Each switch has 3-positions; LINE, OFF and GEN (generator). In the LINE position, utility power feeds the selected circuits. In the GEN position, generator power feeds the selected circuits. To switch from LINE to GEN, the switch is passed through the OFF position. This allows a positive break to occur, which prevents sparking, arcing or short circuits that might be created if the positive break was not part of the system.
Individual circuit protectors protect each selected circuit from overload. This allows a larger generator to be connected to the transfer switch without the transfer switch being overloaded.
|.Transfer Switch Operation |
Offers "Break" then "Make" switches
Only pre-wired circuits can be powered protecting against overload.
Each circuit is protected ˆˆ circuit protector.
For Large/Industrial Generator Transfer Switches
|For Large or Industrial generators and for applications where all of the home or business will have emergency power available; we offer Large/Industrial Transfer Switches, described below. These switches are can handle various voltages and are generally unlimited in the size available. These switches usually transfer automatically and have a wide range of features including automatic excising, changeable start and stop delay times, changeable cool down times and other features. |
Transfer switches are available fused and with breakers. Special switches are available that allow using more than one generator at a time, switching between multiple generators and other situations.
Click on the pictures below for specific information about the types and sizes available. Most transfer switches are UL listed, and come in a variety of enclosures.
|. We Provide Several Types and Sizes |
Indoor, 25 to 4,000 Amps
Outdoor, 25 to 4,000 Amps
Automatic and Manual
Enclosures of all types
See our ordering guide and catalog. ----> Large/Industrial Transfer Switches
|TRANSFER SWITCH OPERATION - For Large Industrial Home and Business Generators|
The Transfer switch isolates the entire electrical service panel. The Electric Codes in most states require that the building service and Transfer Switch size be the same. If the building has a 200 Amp service the Transfer Switch must also be 200 Amp. This is true even if the generator is smaller in amperage than the building service.
Most Electric Codes also require that the buildings total load cannot exceed the total load that the generator is capable of. This means that you may have to install devices that prevent some circuits from being used if the generator is "on-line".
For all these situations you should utilize the services of a qualified electrician. Improper wiring of equipment can lead to fires, explosions, serious injury and even death.
Large industrial transfer switches have an automatic mode that switches the transfer switch and starts the generator on loss of power and then stops the generator and switches the transfer switch back when power is restored. They also have "OFF" modes so that the generator will not start automatically.
Each switch type and brand has its own features and options. We carry only the top brands of switches including ASCO, Generac, Kohler, Onan and Zenith. All are high quality and field proven to be reliable.
Follow good safety practices at all times! PLEASE ALSO READ GENERATOR SAFETY