Kyle McMillan

About Kyle McMillan

Engineer in charge of PROFINET certification testing and development at the PROFI Interface Center.


PROFINET and OPC UA are two common protocols that have some overlap in the automation and process industries, and understanding which protocol to use in a particular part of a network can be confusing. Should a new plant use PROFINET or OPC UA to implement local control loops? What about performance data for an automation cell?  Which protocol is the […]

PROFINET Communication Channels

PROFINET is great at moving information across a network – we never get tired hammering that message home. But exactly how PROFINET moves that information is still a gray area for a lot of users, and deserves a closer look here. To understand how PROFINET moves information, it helps to keep in mind what kind of information it’s moving.  Does […]

Components: Device, Controller, Supervisor

A PROFINET network can be a complex collection of stations, from digital I/O devices to pneumatic actuators to laser scanners… the list seems endless and grows every day. But within that complex network, all PROFINET components operate within three different roles. They can be either Devices, Controllers, or Supervisors.

PROFINET Supervisors and Supervisor Takeover

In our article on PROFINET Components, we saw that most of the communication in PROFINET flows between Devices and Controllers. Supervisors don’t get much attention because they don’t get involved in production work. However, a PROFINET Supervisor can be a great tool during system commissioning, checkout, and even to troubleshoot when there’s a problem. PROFINET supervisors operate in a similar […]

Isochronous Real-Time (IRT) Communication

When you mention the words “real-time” and “Ethernet” in the same sentence, let alone next to each other, you get some incredulous looks.  Ethernet, by definition, is an open network that allows anyone to transmit at any time – making it a probabilistic transmission medium.  Unless there’s abnormally high bandwidth utilization, Ethernet is built on the assumption that nodes will probably […]

PROFINET Proxies and Gateways

Fieldbus solutions have been in place for decades in most industries, and there’s an incredible amount of knowledge built up around them.  Everything from PROFIBUS to DeviceNet, from 4-20 loops to MODBUS RTU… engineers just graduating with their B.S. degrees were born after most of these automation systems were developed! Migrating these solutions to PROFINET is a common challenge.  Every […]

PROFIdrive Application Class 1

When we talk about PROFIdrive, it’s always fun to use high-speed servos, CNC milling, and 3-D printing as application examples.  But those applications are only some of the ways we use motors in the real world.  Every day, millions of motors and drives are dedicated to pumping, blowing, and turning at a fixed speed.   That’s what Application Class 1 drives […]

PROFIdrive Application Class 3

An Application Class 3 (AC3) PROFIdrive device is a “Positioning Mode” drive, and it builds on the concepts of an AC1 device.  However, instead of commanding a drive to move at a desired speed, now the controller asks the drive to move to a desired position.  An AC3 device, as with AC1, handles all of the feedback from the positioning […]

PROFIdrive Application Class 4

PROFIdrive Application Class 4 (AC4) drives are speed-controlled drives.  Like AC1, a controller can command the drive to spin a a given speed.  However, AC4 drives are typically used with high-performance servos rather than the fans or pump motors AC1 is used with.  Because of this high-performance use case, AC4 drives provide a position control loop and cede some of […]

The PROFIenergy Profile

After learning about what profiles are, it’s time to take a look at one of the several profiles for PROFINET. PROFIenergy is one of the easiest profiles to implement across a range of devices, from cameras to motors. PROFIenergy: A Big Deal PROFIenergy operates as a programming API, allowing application engineers to use common code blocks in PLCs to control […]

System Redundancy with PROFINET

Automation systems have always been designed to meet two key criteria: reliability and availability.  Reliability is the first priority- data that enters the network should pass through it unchanged and should always make it to its destination.  But availability is a more complex problem because it’s not just about moving bits across a network once they’re transmitted.  Instead, availability means […]

Redundancy Terms: S1, S2, R1, R2

System redundancy for PROFINET comes with some strange terminology: S1, S2, R1, and R2 all show up in technical and marketing literature.  They’re usually presented without much context, so we’ll clarify them here. System redundancy relies on the concept of multiple connections to a device or controller to maintain the system in the event of a failure.  In our article […]