Automatic Transfer Switch Supplier

What Are the Pros and Cons of an Automatic Transfer Switch?

An Automatic Transfer Switch (ATS) is the brain of a backup power system. Its core function is simple: to automatically transfer the electrical load from the utility power source to a generator when it detects a failure, and then switch back once utility power is restored. For anyone considering a backup power solution, understanding the advantages and disadvantages of an ATS is the critical step.

AdvantagesDisadvantages

Automatic OperationHigher Initial Cost

Provides seamless, uninterrupted power transfer without any human intervention. This is crucial for critical loads like medical equipment, security systems, and refrigeration.The ATS unit itself, combined with the cost of professional installation, represents a significant upfront investment compared to a manual solution.

Ideal for unattended sites or for homeowners who are away during an outage. The system operates independently, ensuring power is restored even if no one is present to start the generator.If the ATS itself malfunctions, the entire automatic backup system is compromised. A manual bypass is often recommended to allow for service without losing backup capability.

What to Know Before Purchasing a Dual Power Automatic Transfer Switch

Purchasing a dual power Automatic Transfer Switch is a significant decision that impacts the safety and performance of your backup power system. Before making an investment, it's essential to consider several key factors to ensure you select the right model for your needs.

You must determine the electrical load you need to support. The ATS must be rated to handle the total amperage of your critical circuits. Calculate the combined wattage of the appliances you wish to run during an outage (e.g., well pump, furnace, refrigerator, and some lights) to determine if you need a 100-amp, 200-amp, or larger switch. Mismatching the ATS and generator size can poor performance or tripped breakers.

Consider the transfer time. This is the brief delay between utility power loss and the ATS commanding the generator to start and transfer the load. While modern ATS units are fast, typically taking only seconds, some sensitive electronic equipment (like certain medical devices or high-end computing systems) may require a nearly instantaneous transfer. For these cases, you would need to look for a switch specifically designed with a very short transition time.

Decide on the power sensing type. ATS units can monitor single-phase or three-phase power. For virtually all residential applications, a single-phase ATS is correct. However, for commercial or industrial settings with three-phase equipment, a three-phase ATS is mandatory to properly monitor all phases for abnormalities.

Plan for professional installation. The installation involves working directly with your main electrical panel and utility connection, which is dangerous and requires a licensed electrician. They will ensure the ATS is wired correctly, safely, and in compliance with all local electrical codes, which often require a permit and inspection.

Home Power Transfer Switch: Why Does It Fail? What Are the Reasons?

A home automatic transfer switch is a robust device, but like any electro-mechanical component, it is not immune to failure. When an ATS fails, it can leave you without backup power precisely when you need it more. The reasons for failure typically fall into a few key categories.

Contactor or Mechanical Failure: The core of an ATS is a set of contactors—electrically controlled switches that physically move to connect either the utility or generator power. Over years of operation, these contacts can wear down, pit, or weld together due to electrical arcing. The motor or solenoid that drives the switching mechanism can also fail from repeated use or seize up due to a lack of maintenance.

Coil Failure: The transfer switch's operation is initiated by an internal coil that creates a magnetic field to move the contacts. If this coil is exposed to voltage spikes from the utility grid (such as from lightning or power surges) or simply fails due to age and heat, it can burn out. A burned-out coil will prevent the ATS from receiving the signal to transfer, rendering it inoperative.

Control Board Malfunction: The "brain" of the ATS is its electronic control board. This board constantly monitors utility power and sends commands to the transfer mechanism. Power surges, moisture, dust, or corrosion can damage the sensitive components on this board. A faulty control board may not detect a power outage, may not send the start signal to the generator, or may get stuck in an error state.

Lack of Maintenance and Environmental Factors: An ATS installed in a harsh environment is more prone to failure. Dust and dirt can impede moving parts. Moisture can corrosion on electrical contacts and circuit boards. Insects or small animals nesting inside the enclosure can cause short circuits. Furthermore, if the ATS is never manually tested on a regular schedule (as recommended by manufacturers), these issues can develop unnoticed until an actual power outage occurs.