To address this question we must first understand what AC and DC mean. AC means alternating
current and DC means direct current. In AC or alternating current the current changes direction.
AC current can travel further distances and the voltage can be bumped up and down.
AC power utilizes transformers to control the amount of power delivered and the direction the power
flows. AC power is a stronger current, but it cannot be stored. In DC power, the power only
flows in one direction. DC power is found in batteries and the voltage is constant and cannot be
changed. DC power does not travel very far without losing its strength and DC power can be
AC Garage Door Motors
AC motors have been used in the garage door industry much longer than DC motors. AC motors
are typically larger, heavier and louder motors requiring more components to control the
amount of electricity delivered to the motor. AC motors can require costly repairs to keep them
AC motors, in most cases, are so large and heavy that they do not allow
for the newer components today’s consumers want in their garage door openers. These new
components include battery backups and MyQ technology.
DC Garage Door Motors
DC motors are becoming the standard in garage door motors. DC motors are smaller, lighter
and quieter than AC motors. AC motors use an electronic circuit board to control the amount of
power delivered to the motor. These circuit boards can allow the motor to have a soft open and
This function speeds up and slows down the motor at different phases in the
open and close function, allowing the soft open and close. Genie first used a DC motor in a
garage door opener in 1994 while Liftmaster did not use DC motors until 2000. DC motors once
utilized brushes in its motors, but now DC motors utilize brushless designs, making them last
In our technology based society, people are wanting more and more options to
make life simpler. Some of these technologies include the MyQ technology which allow the
owner to open and close the garage door from a smart phone or tablet. It can also include
controlling lighting and other household appliances as well as locking and unlocking the house.
This technology requires added space in the garage door opener unit. The smaller and lighter
weight DC motors in garage door openers allows for the adding of these functions. Many
people also want the convenience of having a battery backup system. The battery backup
system allows the owner to open and close the garage door using the opener during periods of