from the Manufacturer
Become a Distributor
on volume purchases
at our Miami office
A generator transfer switch is a critical safety device that connects your generator to your home’s electrical system. It prevents dangerous backfeeding to the utility grid, allowing you to safely switch from utility to generator power during an outage without risking electrocution or fire.
Key Generator Transfer Switch Types:
Common Sizes by Generator Output:
During a power outage, running extension cords from a portable generator is inconvenient and a security risk, requiring open windows or doors. More importantly, plugging a generator directly into a home outlet is illegal and extremely dangerous.
The National Electrical Code (NEC) legally requires a three-position switch (LINE-OFF-GENERATOR) to prevent backfeeding, which can electrocute utility workers, damage your generator, and cause fires.
Whether you’re a facilities manager ensuring business continuity or a homeowner preparing for hurricane season, choosing the right transfer switch means the difference between safe, reliable backup power and potential disaster.
Handy generator transfer switch terms:
When a storm knocks out power, a generator transfer switch is the device that keeps your lights on and refrigerator humming. It transforms your generator from a standalone appliance into a seamless backup power solution for your home, eliminating the need for extension cords run through open windows and doors.
A generator transfer switch acts as a safe bridge between your home, the utility grid, and your generator. During an outage, it disconnects your home from the grid and connects it to the generator. When power is restored, it switches back. This system allows you to power hardwired appliances like your furnace, well pump, and smoke detectors directly through your home’s electrical panel.
A transfer switch is not just convenient; it’s necessary for safety and legally required by the National Electrical Code. It ensures your generator and utility power can never be connected simultaneously, preventing a dangerous situation called “backfeeding.” For more details, check out our Helpful Info on Generator Transfer Switch Options.
Plugging your generator directly into a wall outlet is illegal and extremely dangerous. This shortcut, known as backfeeding, has severe consequences.
Backfeeding sends electricity into the grid, energizing power lines that utility workers believe are dead. This creates a lethal hazard for linemen working to restore power. The risks also include frying your electronics when utility power returns, burning out your generator, and damaging utility equipment, which can prolong the outage for everyone. Overloaded circuits can also overheat and start fires.
To prevent this, the NEC legally requires transfer switches to have a three-position design (LINE-OFF-GENERATOR), ensuring there is always a safe “off” position between the two power sources. The cost of a proper transfer switch is minor compared to the risk to lives, your home, and potential lawsuits.
Choosing a generator transfer switch is like picking between a manual and an automatic car. Manual switches require your input, while automatic switches handle the work for you. Both get the job done, but the experience differs.
Let’s break down the key differences:
| Feature | Manual Transfer Switch | Automatic Transfer Switch (ATS) |
|---|---|---|
| Cost | Less costly ($200-$600) | More costly ($600-$2,000+) |
| Operation | Requires user intervention (flipping switches) | Automatic; no user input needed |
| Installation | Simpler, less complex electronics | More complex, typically requires professional electrician |
| Best Use Cases | Portable generators, less frequent outages, budget-conscious users | Standby generators, frequent outages, critical facilities (hospitals, data centers), convenience |
| Seamlessness | Brief power interruption during transfer | Near-seamless transition, minimal power interruption |
The choice depends on how hands-on you want to be and your area’s outage frequency. For occasional outages, a manual switch is a great, budget-friendly option. For frequent outages or the convenience of automation, an ATS is worth the investment.
A manual transfer switch is your backup power’s control center, and you are the operator. When the power goes out, you must be present to follow a specific sequence. The process involves turning off all circuits, connecting your portable generator via a heavy-duty cord, starting the generator, and then flipping the main breakers from the utility to the generator position. Finally, you turn on circuits one at a time to avoid overloading the generator.
Manual switches are straightforward and cost-effective ($200-$600). Their simple design makes them reliable and well-suited for portable generators and areas with infrequent outages. Our McPherson Controls line offers robust manual transfer switches that provide professional-grade performance.
An automatic transfer switch (ATS) is a vigilant guardian for your power supply. It constantly monitors utility power and acts immediately when an outage occurs. When power fails, the ATS detects the outage, signals your standby generator to start, and once it’s stable, transfers the electrical load in seconds. The transition is so seamless your appliances may not even flicker.
When utility power returns, the ATS senses it, transfers the load back, and shuts the generator off after a cool-down period. This hands-free operation is ideal for frequent outages, for homeowners who may be away, and for critical facilities. They are the standard for standby generators. Learn more in our guide on How Automatic Transfer Switch Works.
Our Automatic Transfer Switch for Generator systems feature advanced options like programmable displays and remote monitoring, ensuring your backup power is always ready.
Choosing the right generator transfer switch requires matching it to your generator, your home’s electrical needs, and the circuits you want to power during an outage. This guide will walk you through the key considerations.
Getting the right switch is crucial. An incorrectly sized switch can’t handle your generator’s power or may trip when you need it most.
Sizing your transfer switch correctly is critical. An incorrectly sized switch can be unsafe or inefficient.
For manual transfer switches, the rule is simple: match your generator’s largest outlet. A generator with a 30-amp outlet needs a 30-amp switch. If it has a 50-amp outlet, you need a 50-amp switch.
Automatic transfer switches must match your home’s main electrical panel. For a 200-amp main panel and whole-house coverage, you need a 200-amp ATS, regardless of your generator’s wattage, to safely handle the potential electrical load.
Remember to calculate your wattage needs. A 5,000-watt generator might power six essential circuits, while a 10,000-watt unit can handle 10 or more. Wattage meters on your transfer switch are invaluable. They display real-time power usage, helping you manage your load and prevent overloads. For detailed guidance, check out our guide on generator transfer switch options.
A generator transfer switch is part of a complete system. Understanding its components helps you make an informed decision. Key components include the transfer switch itself and a power inlet box. The inlet box is mounted outside, providing a safe, weatherproof connection point for your generator cord, which improves convenience and security.
You’ll also need a heavy-duty generator cord. The switch includes main breakers for safely switching power sources and, on manual models, circuit selectors to control which circuits receive power.
Modern switches offer advanced features for effortless management. At MTS Power Products, our switches come with programmable displays for complete system control. Remote monitoring capabilities offer ultimate convenience. Our advanced ATS controllers let you check your power status from your phone, providing peace of mind from anywhere.
Our McPherson Controls line integrates these features with high safety standards and professional quality, ensuring your backup power is reliable when you need it most. Explore our range of ATS Controller options to see how advanced power management can work for you.
A generator transfer switch is only as good as its installation and maintenance. Both are critical for safe, reliable operation.
The location of your generator transfer switch is a key decision that affects cost and performance. Install the switch near your main service panel (within 2 feet is ideal) to minimize wiring costs. For outdoor installations, especially in unpredictable Florida weather, use a weatherproof NEMA 3R enclosure to protect your investment.
The wiring process is complex and involves connecting the switch to your main panel, selected circuits, and an outdoor power inlet. Safety is paramount: always turn off all power and verify circuits are de-energized before beginning any work. For a visual guide, see this tutorial on installing a transfer switch, but electrical work is best left to professionals.
The National Electrical Code (NEC) mandates a three-position switch (LINE-OFF-GENERATOR) to create a mechanical and electrical interlock. This prevents dangerous backfeeding by ensuring utility and generator power can never be connected simultaneously.
Local permits and inspections are non-negotiable. Most jurisdictions require a licensed electrician for installation, along with permits and inspections to ensure the work is done safely and to code. The bottom line: professional installation by a licensed electrical contractor is essential. They understand all relevant codes and ensure your system is safe and compliant. Even our high-quality MTS Power Products equipment requires proper installation to function safely.
Regular maintenance ensures your generator transfer switch will be ready when you need it.
Always follow your owner’s manual for specific maintenance schedules to ensure the best performance and longest life for your switch.
Here are answers to some of the most common questions we receive about generator transfer switches.
While the satisfaction of a DIY project is understandable, installing a generator transfer switch is a job for a professional. Please do not attempt this yourself. Transfer switches connect to your home’s main electrical panel and involve high voltage. A small mistake can lead to electrocution, fire, or costly damage to your electrical system and generator.
Furthermore, most jurisdictions legally require a licensed electrician for this work, which also requires permits and inspections. Professionals know the local codes and safety standards to ensure a correct and safe installation. Professional installation is an investment in safety and peace of mind.
The number of circuits a transfer switch can power depends on several factors. Manual transfer switches typically handle 6 to 10 circuits. Whole-house automatic systems are rated for your entire electrical service (e.g., 100 or 200 amps).
Crucially, your generator’s wattage capacity is the ultimate limiting factor. A switch may have 10 circuits, but your generator’s output determines how many you can use simultaneously. You must manage your electrical load carefully. Wattage meters on transfer switches are incredibly helpful for this.
Your generator transfer switch has built-in protection. If you try to draw too much power, the circuit breaker for that circuit will trip. This safety feature prevents damage to your generator and home electrical system.
To fix this, reduce your electrical load by turning off some devices, then reset the tripped breaker. Frequent tripping indicates that your generator may be too small for your needs or that you are trying to power too many devices at once. Wattage meters can help you monitor usage in real-time to avoid overloads.
Pro tip: Turn on circuits one at a time when switching to generator power to prevent an initial power surge from tripping breakers.
Choosing the right generator transfer switch is an investment in peace of mind, ensuring your family stays safe and comfortable during a power outage. We’ve covered the differences between manual and automatic switches, the importance of proper sizing, and the necessity of professional installation and regular maintenance. The key is to match the switch to your generator and your power needs.
Professional installation is legally required in most areas to prevent the dangers of backfeeding and ensure the safety of your home, family, and utility workers. Regular maintenance ensures your system is ready when you need it most.
At MTS Power Products, we meet unique power needs with professional-quality generators, control panels, and our specialized McPherson Controls line of transfer switches. From our Miami location near the airport and port, we deliver worldwide with the service of a local company.
Our transfer switches feature programmable displays and remote monitoring for improved control and peace of mind. We’ve built our reputation on high safety standards and reliable products that work when you need them.
Don’t wait for the next outage to find yourself unprepared. Your family deserves the security that comes with reliable backup power.
Find the right Automatic Generator Transfer Switch for your needs
