If you’re thinking of connecting an electrical generator to your household to provide backup power during an outage, there are different options. One of the simplest, most flexible and most economical uses something called a manual transfer switch connected to a portable generator.
Besides being far cheaper than the alternative of a stationary home standby generator, a portable generator with manual switch offers advantages. The system is easier to install and you can easily upgrade to a larger portable generator in the future. You can also use your generator in other locations and swap in a different generator if your current one breaks down.
I’m having a manual transfer switch installed at my place, and it’s not difficult to understand how they work. The switch itself is built inside a small electrical panel that directs generator power to essential circuits in your house during an outage — the circuits that you most want to function when the grid goes down. This typically includes lighting, wall outlets, a furnace or air conditioner, a water pump (if you’re on a well), and perhaps internet equipment, a sump pump or a sewage pump.
Many of these items don’t have plugs or outlets so they can’t be connected to a generator using an extension cord. This is possibly the greatest advantage of a manual transfer switch; you can get power to essential appliances that can only get their power through the electrical panel.
Portable generators don’t put out enough power to energize everything in most homes, so one way or the other you’ll need to choose which circuits to power. Installing a transfer switch just means you make this decision ahead of time as circuits are re-routed into the manual transfer switch panel during installation.
Switchless connections illegal
It is dangerous and illegal to connect a generator directly to hard-wired circuits in your home without a switch because of the very real hazard it poses to electrical workers. Don’t do it. Line workers have died from this kind of thing. This is why various transfer switch options were developed.
Installing a transfer switch is work for a licensed electrician, but the concept is simple and you’d be wise to understand what’s involved. Wires connected to existing breakers for essential circuits in your current electrical panel get disconnected and reconnected to different breakers within the transfer switch panel itself.
A weatherproof outlet comes with most transfer switch kits (including the Champion unit I have) and typically gets installed on the outside of an exterior wall. When grid power goes down, you need to do two things:
- Connect your generator to the weatherproof outlet using the special power cord provided with the unit, then get the generator running.
- Flip ON the manual transfer switch inside your home to disconnect the panel from the grid. This simultaneously establishes a connection between your generator and those essential circuits you re-routed into the transfer switch panel, all with a guaranteed disconnection from the grid.
Both functions are handled by the same two-position toggle switch. Fuel-powered generators must always be used outdoors, far from occupied buildings with the exhaust pointed away from people, animals and buildings.
The Champion TS 30 unit I have at my place costs $599. It can handle 30 amps at 240 volts, which translates to 7,200 watts of total power delivered — large enough to handle the output of most portable generators for household backup. The unit comes with a weatherproof outlet, a power cord to connect a generator to the port, five 120-volt 15-amp protected circuits, one 120-volt 20-amp protected circuit, and one 120/240-volt 30-amp protected circuit.
