Person driving a dark blue riding mower while cutting grass

The Capability Edge: Brushless Motors and Sealed Connectors in E-Mower Applications

 

The new SBS®X-Pro Sealed Connector from Anderson Power™ provides a powerful and convenient maintenance interconnect solution for large outdoor electric mowers.

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Engineers know that commercial lawnmowers are going electric. In 2023, Honda announced it would discontinue all gas-powered mowers in favor of battery-powered designs. That same year, Ryobi launched an 80V line of e-mowers and touted the benefits of its quieter operation and lower maintenance requirements. Mower brands like Toro, Gravely, and Mean Green also offer a growing variety of commercial-grade electric lawnmowers. In fact, the e-mower industry is expected to grow from $9.28B in 2024 to $14.52B in 2033, driven by consumer demand for eco-friendly equipment and stricter environmental regulations.

 

How can engineers prepare for this technological shift? Today’s e-mowers require rugged connector solutions that can withstand harsh outdoor environments while providing enhanced signaling and power capabilities that support their advanced designs. Additionally, new connector solutions offer easier maintenance of e-mowers with brushless DC motors.

 

HOW SHOULD ENGINEERS ADAPT TO BRUSHLESS MOTORS?

Most e-mowers rely on brushless DC motors (BLDC) to power their operation. Originally invented in 1962, BLDCs did not become widespread until the late 1980s when new engineering advancements helped them overcome their limitations in power generation.

 

BLDCs offer a more efficient replacement to brushed DC motors. Traditional brushed motors rely upon the actual mechanical interaction of physical brushes with copper windings to transfer current from coil to coil. In contrast, BLDCs use an electronic device called a controller to shift current between three different power connections in sequence. Instead of relying on the motion of physical brushes, this electronic shifting is what generates a dynamic magnetic field that interacts with the rotor’s magnets and causes it to spin.

 

The electronic speed controller manages the power and signals going to-and-from the motor in order to control the motor’s speed and torque. Many commercial-grade brushless e-mowers use their speed controllers to regulate power output, both saving energy and preventing damage to the motors. For example, the controller might regulate power depending on the thickness of the grass being cut. Using this smart power management, owners can reduce the amount of total power used and help their e-mower last longer on a battery charge.

 

The main downside to brushless motors is that they initially cost more to purchase than brushed motors due to their integrated electronics. However, this cost disparity often evens out over time due to reduced maintenance requirements with brushless motors.

 

The benefits to BLDCs are numerous, including:

  • Superior energy efficiency. Brushless motors offer superior efficiency by eliminating energy losses caused by friction and heat from the brushes’ movement. In general, brushed motors operate at 75 to 80% efficiency, and brushless motors achieve 85 to 90% – though the exact comparison differs depending on motor configuration and other factors.
  • Extended battery lifespan. BLDCs can generally withstand more charging cycles. Physical brushes will wear out as they continuously rub against the motor’s commutator. Brushless motors avoid this issue entirely, though other factors like charge/discharge cycles and environment temperature also impact battery longevity.
  • Noise and vibration reduction. The movement of physical brushes generates EMI (electronic noise) and vibrations, so brushless motors deliver quieter operation. For e-mowers, this is a particularly attractive trait because it leads to a reduction in cutting noises.
  • Compactness. Since BLDCs do not incorporate physical brushes, their design can be made more compact than brushed motors rated for similar output power.
  • Connectors are an essential part of any e-mower design with a brushless motor. They can be found between many different components on a mower, including from the controller(s) to the battery, from the battery to the charger, from the wheel motor(s) to the controller, from the blade motor(s) to the controller, and from the controller to mower accessories.

 

One connector application is the charging port, which requires an integrated connector to transfer power from an outlet to the mower’s lithium-ion batteries. However, another innovative connector application is entering the market that makes mower maintenance easier than ever.

 

WHAT SEALED CONNECTORS DO E-MOWERS REQUIRE?

This application involves the internal connection between the mower’s power source and the motors and controllers. This connection is traditionally hardwired, which makes lawnmower assembly and repairs more complex and time-consuming. Issues that involve troubleshooting – such as loose connections, failed wires, or bad sensors – as well as motor and blade maintenance often require accessing internal wiring and disconnecting the battery. This process can require a technician with training and specialized tools.

New connectors are entering the market that simplify this process. Known as maintenance interconnects, these connectors replace the wire connecting to each of the three power lines.

 

Users can simply unmate the connector to disconnect power from the battery – no specialized tools required.

 

The connector also provides users with the ability to easily drop the mower’s deck, which is the housing that encloses the cutting blades. This easy access enables owners to simply release the required connections to begin maintenance or to replace the deck with another while the original is being repaired. Both situations reduce downtime for the mower.

 

Maintenance interconnects thus offer e-mower manufacturers and owners an edge in convenience when servicing/troubleshooting equipment.

POWER AND SIGNALING CONSIDERATIONS FOR DESIGN ENGINEERS OF BRUSHLESS EQUIPMENT

Another important connector consideration for brushless designs involves enhanced power and signaling. Typical DC applications require two power connections. However, BLDCs require three DC power contacts from their internal maintenance interconnects. This is because of the three-phase windings inside a brushless motor.

Additionally, modern e-mower designs often require enhanced signaling power. Signals are the physical, auxiliary pins within a connector that are used to transfer data and keep tabs on the batteries and electrical loads like motors. Signals might be used to monitor battery lifespan, mating cycles, internal temperature, control the brushless sequencing, and more. Such data is useful to maintain peak battery and motor performance and respond proactively to any issues.

 

One additional note is that most typical DC applications require low-resistance connections to maintain efficiency and prevent overheating. BLDCs are no different; they also need to maintain these characteristics alongside their higher demands for both power and signaling.

As e-mowers integrate lithium-ion batteries and more advanced intelligence, the need for signaling is continuing to grow. Smaller applications like push mowers might need only four signals, but today’s heavy-duty electric riding mower designs increasingly require six or even up to eight signals.

 

To support the needs of outdoor power equipment with brushless motors, connectors must deliver the desired levels of power and signaling and remain sealed against water/dust intrusion. Some connectors that deliver three power contacts lack robust signaling capabilities, requiring OEMs to purchase separate signaling connectors. Designs that combine high power and advanced signaling into a single connector should be preferred, since they provide a convenient, all-in-one connector for engineers that maximizes space and resources.

The SBS®X Pro Sealed Connector from Anderson Power™ combines 3 power contacts with 8 signals to deliver industry-leading capabilities for large outdoor equipment and support for maintenance interconnects within brushless motor designs.

 

CONNECTOR HOUSING CONSIDERATIONS FOR OUTDOOR, RUGGED ENVIRONMENTS

E-mower connectors must also be able to brave the elements in outdoor environments, such as withstanding damp grass or blowing dust. Two factors to consider in outdoor power equipment (OPE) connectors include:

  • IP Ratings. An IP65, IP67, or IP68 rating indicates a connector is capable of withstanding dust and water exposure – an important feature for e-mowers and other OPE applications. Specifically, an IP65 connector is dust-tight and remains sealed against mist and rain, while an IP67 connector is dust-tight and can withstand water submersion at a depth of one meter for up to 30 minutes. IP68-rated connectors offer even greater water resistance than IP67, though the actual specifics depend on the manufacturer

  • Weatherability. The UL 746C standard classifies materials for UV and water resistance. Design engineers should look for an F1 rating in their connectors, which signifies the connector material can withstand prolonged exposure to the sun in outdoor environments.

The SBS®X-75A Sealed Waterproof Connector from Anderson Power features an IP68 rating for premium water resistance and offers a flip-top cover option for panel mount applications that protects the connector housing with a sleek, space-saving cover.

 

TAKING BRUSHLESS E-MOWERS INTO THE FUTURE

 

In 2021, about 56% of the 38 million outdoor power equipment products shipped in the United States were zero-emission. That number will only increase as the market shifts toward sustainability. For the lawnmower industry, this means more electric models powered by lithium-ion batteries and less traditional gas combustion models.

 

Modern connector solutions are evolving to meet the demands of commercial-grade electric mowers. Sealed connectors feature high IP and weatherability ratings to ensure they can withstand the rigors of outdoor mowing environments. Maintenance interconnects provide an innovative way to access the internals of brushless equipment, making troubleshooting battery issues easier than ever. Connectors that provide greater power and signaling are also entering the field, responding to new tech-heavy designs that demand up to eight signals and three power contacts.

 

As design engineers embrace an electrified future, brushless motor equipment will only continue to advance in power demands and technology. Connectors that offer a true capability edge – delivering powerful, durable, and innovative performance – will become even more essential.

The SBS®X-75A from Anderson Power features 2 power contacts and up to 6 signals to provide a powerful, sealed connector solution for electric lawn and garden applications.

 

 

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