Transfer of Power

By: Joseph Truini (Page 5 of 5)

photo by: Ron Chapple

Photo courtesy Campbell Hausfeld

A six-circuit transfer switch is designed for a 5,000W generator, like this Campbell Hausfeld unit (Model GN5031, $899).

Photo courtesy Makita

This 4,800W Makita generator ($2,229) has four different receptacles and push-button electric starting.

Photo courtesy Generac

This powerful 7,500W Generac unit ($1,899) creates enough juice to power a 10-circuit transfer switch.

Photo courtesy Craftsman

The 7,500W, 15-hp Craftsman generator ($1,799) runs for more than seven hours on its 5-gallon tank of gas.

Photo: Geoffrey Gross

Photo: Geoffey Gross

Step 1: The transfer switch is placed beside the main service panel; its wires are pulled up through the bottom of the panel.

Photo: Geoffrey Gross

Step 2: Each wire from the transfer switch is connected to an existing circuit breaker inside the main electrical panel.

Photo: Geoffrey Gross

Step 3: At a junction box, a power cord is joined to a nonmetallic cable that runs to an outside wall and the power inlet box.

Photo: Geoffrey Gross

Step 4: A hole saw cuts an access hole for mounting the power inlet box to the cable running from the junction box.

Photo: Geoffrey Gross

Step 5: The Generator is plugged into the power inlet box. Power flows through the transfer switch to the designated circuits in the house.

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When Only Full Power Will Do

If your neighborhood seems to be the last to have its power restored or you just like the idea of having all circuits available without even venturing out in inclement weather to start your generator, you might want to consider getting a whole-house, standby power unit installed.

Standby generators offer the ultimate in blackout protection by supplying electricity to your entire house, not just to a few selected circuits. These personal power plants come in various sizes up to 40,000W, and run on natural gas, propane, or diesel fuel. They get installed outside on a concrete slab or pier blocks and are wired through a transfer switch to the main electrical panel. When the power goes out, there's a slight delay of 15 to 20 seconds, then the generator automatically kicks on and continues running until power is restored.

Of course, you pay a premium for all this convenience and peace of mind. The average-size home will require a 12,000W to 15,000W generator, which costs $6,000 to $8,000. Installation can easily run another $2,000.

For specific information regarding generator size and installation costs, consult a local electrician or check out www.generac.com.

And, finally, the installation of a whole-house generator must be specifically designed for your home. Disregard any price quote given by an electrician who hasn't personally inspected your electrical system and site.