Medium & High Voltage Motors

For heavy-duty drives – large pumps, compressors, fans, mills and rolling mills – low-voltage motors quickly become impractical. As power rises, so does line current, and with it cable size, losses and cost. Moving up to medium or high voltage lowers the current, improves efficiency and keeps cabling manageable. The challenge is getting a motor built precisely for the load, the duty and the environment.

OME Motors designs and builds custom medium voltage motors and high voltage three-phase induction motors engineered around your application. Available with squirrel-cage or wound-rotor construction and a modular cooling system, they are built to IEC standards for the most demanding industries – in both safe and hazardous-area versions.

Medium voltage vs high voltage electric motors

In North America, low voltage generally means up to 600 V. Medium voltage covers roughly 2,300 V to 6,900 V – with 4,160 V among the most common classes – while high voltage refers to the classes above that. OME builds motors across the medium and high voltage range and matches the winding to the exact system voltage, so the motor is optimized for your network rather than adapted to it.

Squirrel-cage and wound-rotor (slip-ring) construction

OME medium and high voltage motors are available with two rotor types. The squirrel-cage rotor is rugged and virtually maintenance-free, the default choice for most applications. The wound-rotor (slip-ring) design brings the rotor windings out to external resistors, delivering high starting torque with low starting current – ideal for high-inertia loads such as mills and crushers. Both use a laminated, pressed and protected core for excellent insulation, mechanical strength and long service life. For heavy slip-ring duty, see the OMA high voltage series.

Cooling systems and construction options

A modular cooling system – IC01, IC411, IC611 or IC81W depending on the model (OMV, OMVP, OMVK, OMVKS) – is matched to the duty and environment. Roller or sleeve bearings, left- or right-hand terminal boxes, and stator-winding and bearing temperature sensors are available on request. Wide customization and any required construction form are part of the standard OME offering.

VFD-ready operation

OME medium and high voltage motors are VFD-ready: running a motor on a variable frequency drive (VFD) / frequency converter improves process control and cuts energy cost over the life cycle. For VFD duty we specify appropriate insulation, bearing protection and, where needed, temperature sensors to ensure reliability throughout the motor’s service life.

Applications and industries

OME medium and high voltage motors are built for cement plants, steel mills, power generation, water purification, treatment and desalination, sugar factories and wind power – and for both safe and explosive-atmosphere areas. They drive pumps, compressors, boilers, conveyor belts, fans and blowers, mills, crushers and shredders, rolling mills and other heavy-industry machinery.

FAQ – Medium & High voltage motors

What voltage is considered medium voltage vs high voltage for a motor?

In North America, low voltage generally means up to 600 V, medium voltage covers roughly 2,300 V to 6,900 V (with 4,160 V very common), and high voltage refers to higher classes above that. OME builds motors across the medium and high voltage range and matches the winding to the exact system voltage.

What is the difference between a squirrel-cage and a wound-rotor (slip-ring) motor?

A squirrel-cage motor has a rugged, maintenance-free rotor and is the default for most applications. A wound-rotor (slip-ring) motor brings the rotor windings out to external resistors, allowing high starting torque with low starting current, useful for high-inertia loads such as mills and crushers. OME offers both, including the OMA slip-ring high voltage series.

Can medium and high voltage motors run on a VFD?

Yes. OME medium and high voltage motors can operate with a variable frequency drive (VFD) / frequency converter for precise speed control and energy savings. For VFD duty we specify appropriate insulation, bearing protection and, where needed, temperature sensors to ensure reliability over the life cycle.

Characteristics and operating conditions of high voltage motors and medium voltage motors

The high voltage electric motors and medium voltage electric motors are equipped with a laminated core which, before being mounted in the frame, is compressed and protected and then pressed. These particular construction procedures guarantee that the high voltage motors and medium voltage motors of OME Motors have excellent insulating performance, greater mechanical resistance, better resistance to humidity and a long life.
The rotor cage is made of silicon steel and is equipped with copper bars on demand. Furthermore, the rotor is made by a process of Silicon Steel casting and subsequent welding, two phases that are necessary to guarantee maximum reliability and perfect balancing. Depending on the power and speed of the electric motors or based on the specifications required by the customer, roller or bushing bearings can also be used. The main terminal block is located on the right side of the motor, but can also be placed on the left side, according to specific needs. Both the inside and the outside of the terminal box are equipped with separate terminals.

At the user’s request, the stator winding and the bearings can be equipped with sensors for measuring the temperature, ensuring the operation of the motor in safety and reliability over time. Finally, a high voltage electric motor can also work with a frequency converter, thus improving cost savings throughout the life cycle of the device.

Advantages of high voltage motors and medium voltage motors

Custom designed and manufactured using the best performing and innovative materials, these electric motors have technical features that can provide numerous advantages, such as:

Wide possibility of customization, customizable design based on needs, availability of any construction form.
Extreme lightness, despite its large size.
Maximum efficiency, consistent performance and reliability over time.
Easy assembly and maintenance.
High flexibility in use.
Low noise and low vibrations.
Compliance with international IEC standards.

Areas of usage for high voltage motors and medium voltage motors

OME produces electric motors for safe environments, but also for work areas with explosive atmospheres. In fact, these devices are used in the most disparate sectors, from cement factories to steel mills, from power plants to water purification, treatment and desalination systems and from sugar factories to wind energy generation plants. Furthermore, high voltage motors and medium voltage motors are ideal for application and operation with pumps, compressors, boilers, conveyor belts, fans and blowers, mills, crushers and shredders, laminators and equipment for steel plants, turbines and generally all the machinery present in the heavy industry. Finally, these motors can be manufactured with a squirrel-cage rotor or with a wound rotor.