Nidec Motor Corporation Announces Industry Leading Upgrades to its Vertical HOLLOSHAFT® Inverter Duty Motors

Nidec Motor Corporation Announces Industry Leading Upgrades to its Vertical HOLLOSHAFT® Inverter Duty Motors

OCT 01, 2012

St. Louis, MO (October 1, 2012)— Nidec Motor Corporation is again leading the way in the vertical motor industry by introducing its new U.S. MOTORS® brand line of inverter duty vertical motors, which include a bearing protection system.  This is the first vertical motor of its kind to include a shaft ground ring.  This system is available on 40 horsepower and above Vertical HOLLOSHAFT® motors.  Vertical motors 100 HP and larger also include an insulated bearing to prevent circulating and other bearing currents.

One of the first to recognize the need for special inverter duty insulation systems, the company began manufacturing U.S. MOTORS brand horizontal motors with an Inverter Grade™ Insulation System in 2002.

The addition of a shaft-grounding ring on vertical motors reduces damage that can sometimes result from voltage spikes caused by variable frequency drives powering the motors.  The ring short-circuits the current that can ruin the bearings.

Bearing failure results in thousands of dollars in repairs and costly downtime for the motor.  End users in the water/wastewater and agriculture industries will now have a “pre-emptive strike” that will greatly minimize the risk of such damage, and increase motor life.

“Much time, effort, research and testing went into solving the winding and thermal issues with the application of inverters on vertical motors.” said Tim Albers, director of marketing,  Nidec Motor Corporation.  “We are very proud of the advancement we’ve made on the Vertical HOLLOSHAFT® performance.” concluded Albers.

The new 40 HP and above Inverter Duty Vertical HOLLOSHAFT motors are rated NEMA PREMIUM®* and include thermostats which provide over-temperature protection. 

For more information about U.S. MOTORS brand Inverter Duty Vertical HOLLOSHAFT motors, Visit         


About Nidec Motor Corporation:  Nidec Motor Corporation (NMC) is a leading manufacturer of commercial, industrial, and appliance motors and controls.  The NMC product line features a full line of high efficiency motors, large and small, which serve Industrial, residential and commercial markets in applications ranging from water treatment, mining, oil and gas and power generation to pool and spa motors, air conditioning condensers, rooftop cooling towers and commercial refrigeration.    It also makes motors, controls and switches for automotive and commercial markets.   Brands include U.S. Motors®, SR Drives®, Hurst®, Rescue®, ECOTECH EZTM.

Nidec SR Drives Ltd, a Nidec subsidiary, is based at the Nidec Motor UK Technology Centre in Harrogate, UK and operated by NMC specializing in the design and development of new products using advanced brushless motors and controls with a primary focus on SR technology. 

Parent company Nidec Corporation (NYSE:  NJ) is the world's leading manufacturer of small precision motors, including motors used in hard disk drives and optical disk drives.  The company has extended its focus beyond the information storage motor market to the home appliance and automotive markets, where it sees high future growth potential.  For more information, visit


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