Motor Regulations and System Engineering

Starting next year, gear motors, brake motors and inverter duty motors—which had previously been excluded from the Department of Energy’s NEMA Premium regulations—must now meet the standard.

U.S. federal motor efficiency standards began changing back in 2010, requiring that all new motors built since the implementation of the Department of Energy’s Energy Independence and Security Act of 2007 must adhere to the NEMA Premium high efficiency standard. According to NEMA (National Electrical Manufacturers Association), the NEMA Premium requirement is estimated to save 5,800 gigawatts of electricity over 10 years (by 2020), which translates to preventing nearly 80 million metric tons of carbon dioxide into the atmosphere —the equivalent of keeping 16 million cars off the road.

Though initially implemented in 2010, a few motor types, such as gear motors, brake motors and inverter duty motors, were excluded from meeting the NEMA Premium requirement—until now.

During a recent meeting at Siemens’ gear motor assembly plant in Greenville, S.C., Rich Mintz, senior market development manager for Siemens Industry’s gear motor business segment, explained that, as of June 1, 2016, these previously excluded motor types would now also fall under the NEMA Premium requirements.

Mintz noted that most motors, when they are redesigned to meet higher efficiency requirements, usually end up with a bigger footprint due to the different materials used. However, he pointed out that Siemens new high efficiency Sinamics G110M gear motor with an integrated drive has no appreciable size difference compared to its predecessor. “The motor diameter and the terminal box are the same size,” he said, adding that this adherence to footprint was a major design consideration given the ease of automation system integration goals for the new gear motor drive. “We want end users and system integrators to be able to easily upgrade existing systems with these new, higher efficiency drives without having to redesign their systems or perform complicated retrofitting,” he said.

Featuring protection ratings up to IP66, this new gear motor drive is primarily targeted at material handling applications—such as on conveyors—as well as warehousing, logistics, baggage and cargo handling, parcel shipping and in specific automotive industry applications. Mintz adds that, although Simogear gear motors are mostly used for material handling, they are also used in “the oil & gas and water/wastewater industries, with power ratings up to about 200 hp.”

To make it easier for designers and system builders to integrate gear motors into a variety of control architectures, the G110M features plug connections for onboard I/O and built-in PLC functionality, meaning that simple, automated systems can be built with the G110M without requiring connection to a higher level network. However, the gear motor drive also has integrated Ethernet connections for connecting to any network type, including Profinet, Profisafe, and EtherNet/IP.

Integrated features such as “Quick Stop” and a limit switch function, as well as internal braking resistors and motor brakes—which can be operated simultaneously—make this motor drive system well-suited for conveyor applications, Mintz added. “Gear motors are needed in material handling because you need gear reduction and torque multiplication to properly handle conveyor motion,” he said.

For applications requiring safety technology, the Sinamics G110M offers integrated safety functions such as Safe Torque Off, which can be activated via a fail-safe input or via Profisafe without additional safety monitoring components.

With its upgrades to higher efficiency capabilities in accordance with NEMA Premium, Mintz noted that the new G110M gear motor drive is more expensive than its predecessors, but that the product’s energy savings more than offset the higher cost over the life of the device.

Mintz calculated that, based on a 6,000 hours per year operating schedule (i.e., running 23 hours a day, five days a week) at an electricity cost of $.07/kWh, the price difference return on investment on a 1 hp unit is 3.1 years, 4.5 years for a 5 hp unit, and 2.8 years for a 10 hp unit.

For these estimates, Mintz calculated “the difference between the list prices for our standard Simogear motor, which meets NEMA MG-1 Table 12-11, and a NEMA Premium motor, which meets NEMA MG-1 Table 12-12.” He notes that Simogear motors are standard high efficiency motors (NEMA MG-1 Table 12-11), but since many people use “gear motors that are less efficient [than standard high efficiency motors], their energy savings would be even larger.”

While touring Siemens South Carolina motor assembly plant with Mintz, he explained that all motors assembled there are built to order with a 10 day or less delivery promise. Key to this quick turnaround is Siemens’ online configuration tool for ordering motors, which uses 2D and 3D drawings to help customers design the exact motor they need.

Mintz also noted the Siemens Smart Number system used on its motors, which allows anyone to access the motor’s configuration by scanning that number. He says this scannable ID number is unique to Siemens gear motors and that the “number can also be read via RFID. Plus, the RFID tag is writeable so an OEM can add information to the tag. The tag can be used by an OEM for replacement purposes or by end users to access product documentation.”

See a video explanation of the Sinamics G110M featuring Rich Mintz below.

Companies in this article
More in Motion