Today’s automated equipment and manufacturing processes rely on motion control systems for the highly accurate and repeatable positioning of tooling, stages, products and other machine components.  

Conventional motion control solutions consisting of separate motor and drive components pose challenges to machine builders who must route cables between these components within the space limitations of a control panel or installation area.  

Integrated motors offer a space-saving solution over conventional motor and drive solutions by consolidating the drive and motor into a single package.

Integrated motors provide greater design modularity and allow machine builders to more easily accommodate other critical system components such as material handling mechanisms, sensors, and operator interfaces.

Designers can focus less on the placement and size of control panels and the routing of motor cables, and more on non-motor system components for faster design iterations.

Integrated Servo Motors

Integrated servo motors offer the same performance characteristics as conventional servo motors but in a smaller package as they combine the drive with the motor.  

By eliminating the need for bulky cables to connect the motor to an external drive (see Graphic 1), integrated servo motors reduce the amount of room needed for motion control axes, providing machine builders with more space for greater design modularity.

Eliminating the need for separate drive electronics reduces the size and number of control panels for cost savings. Plus, machine builders no longer need to specify or install an external drive and worry about its compatibility with the motor, placement, or wiring. This supports faster design cycles. Eliminating the external drive from the bill of materials also reduces cost.

The onboard drives of integrated servo motors have the same command interfaces as external motor drives including CANopen, RS-485, Modbus, and Ethernet connections.

Smaller diameter cables required for I/O, DC power, and communications are easier to route and take up less space than motor power and feedback cables.  Operators can wire command signals from the machine controller directly to the integrated servo motor.

Integrated Step Motors with Closed-Loop Control

Open-loop step motors remain a popular solution in automation applications due to their simplicity, excellent positioning, and low cost.  Like integrated servo motors, integrated step motors combine the motor and drive into a single package. Drive electronics are mounted at the rear of the integrated motor with external connections for DC power, I/O, and communications.  

Open-loop step motors are particularly well suited to applications where loads need to move repetitively at fairly low speeds. Many applications require better control than offered by open-loop step motors. One economical solution is switching to a closed-loop step motor.  

Adding an encoder to the integrated step motor, along with servo-control algorithms to close the loop around current, velocity, and position, greatly improves the performance of step motors.

Closed-loop, integrated step motors provide greater acceleration, higher efficiency, higher accuracy, and decreased motor noise compared to traditional, open-loop step motors. Integrated closed-loop step motors are offered in the same NEMA frame sizes as open-loop step motors, so upgrading is an easy process.  

In most applications, simply swapping an open-loop step motor with a closed-loop, integrated step motor provides significant benefits. Integrated step motors also support the same control schemes as conventional step motors such as pulse & direction, analog velocity control, and stored program execution as well as industrial Ethernet control such as EtherNet/IP and Modbus TCP.

Dual-Port Communications

A common feature on many integrated motors, both servo and step motor-based, is dual-port communications.  This means each integrated motor features two separate communication ports, allowing their use in a variety of network topologies including line networks.  

Commonly referred to as daisy-chain connections, connecting integrated motors in a line network means fewer “home runs” of communications cables back to a central control panel or switch. This lowers the overall cable lengths and simplifies cable routing around the machine.  (Graphic 2).

Adding Power Over Ethernet (PoE) Functionality

For single-port communications with smaller integrated motors, particularly those in the NEMA 14 frame size, designers can leverage Power over Ethernet (PoE) technology to further reduce the number of cables in their system.  

The PoE+ standard, which provides 25.5 Watts to the integrated motor, is enough to get full torque and speed performance from these smaller motors.  PoE+ uses standard Ethernet cables such as Cat5 and Cat6 and is supported by most industrial Ethernet switches.  Machine builders also can use injectors.

The benefit of PoE is that DC power and communications to the integrated motor travel over the same Ethernet cable, greatly reducing the number of cables for routing around a machine or piece of equipment.

With support for industrial EtherNet protocols such as EtherNet/IP and Modbus TCP, integrated motors with PoE functionality are ideal for new and existing EtherNet networks on axes that require low levels of torque without sacrificing IIoT capabilities.