Got a motion application with specific in and out-feed requirements?  Let the PowerFlex 527 provide a solution.

The 527 is one of Allen Bradley's more feature-rich offerings as it is a VFD with motion-style programming.

This is excellent for motion system designers as it streamlines commissioning efforts.

The feature set of the 527, however, lends itself to applications beyond a motion setting.

In this article, we will provide an overview of the 527 as well as offer several application ideas that may not be immediately obvious.

The PowerFlex 527

The 527 is the latest offering from the 5-series PowerFlex drives. 

Of note is that these VFDs lack a built-in start/stop with a potentiometer. 

This is because the unit is controlled exclusively with CIP motion commands through a Compact Logix or Control Logix PLC. 

Why do you say?  Because motion applications often need in-feed and out-feed control.

While it is possible to use a motion drive for this, it is often not as cost-effective as using a low voltage drive. 

Most low voltage drives, however,  cannot coordinate with a motion system well. 

The 527 fits into this gap by offering motion-style programming in a cost-effective low voltage drive package.

Top Tips for the 527:

  • Safety over ethernet makes life easier:  The 527 supports Ethernet-based safety.  Less wiring and easier troubleshooting are great additions to a safety network. 
  • Take advantage of the DLR:  use this feature to afford smaller and fewer Ethernet switches.  It also provides more system reliability, a big plus.
  • Motion axis consumption:  Configuring a PowerFlex 527 axis as a position loop counts against the position loop max for a PLC.  Such a configuration, therefore, will warrant the use of a motion-level PLC.  If a 527 axis is configured as a velocity loop or frequency control, however, then the 527 may be paired with a non-motion PLC.

Key Features

All right, we have laid out some of the best features of the 527.

You might, at this point, think of this as a specialty drive that only a few might have interest in.

Let me, however, offer the following observations of the 527’s features and non-motion applications.

Device Level Ring

A device-level ring (DLR) Ethernet topology has two connections per device in a daisy-chain format running back to a source Ethernet switch to form a loop.

This allows for a single failure in the Ethernet loop to occur without losing connectivity to any device.

Not only is DLR fault-tolerant, the fact that the ring may be broken in one place at a time allows for Ethernet cable maintenance and troubleshooting without process interruption.

Motion applications make use of DLR as they greatly benefit from its reliability.

Any process, however, that needs high up-time will also see the benefits of native DLR in the 527.

Large panels with many drives also gain from DLR as it allows for the use of smaller Ethernet switches.

Safety Over Ethernet

Safe torque off (STO) offers critical protection to your workforce as well as increased uptime.

Why not gain these advantages with minimum wiring pulling?

The 527 can provide a hardwired STO connection allowing for the creation of local safety circuits with ease.

A localized safety circuit on a single machine is often well served by this.

When, however, working with a large or complex safety network, an Ethernet-based solution can offer easier installation and troubleshooting.

For example, the most simple safety circuit will require seven conductors.

An on-machine application may not be challenged by this, but an operation using multiple machines and safety gates can become hard to manage and troubleshoot when dozens of conductors need to be installed and routed over long distances.

Ethernet-based CIP safety stands out as a simple means to achieve safety ends when working with a larger and more complex safety system.

Positioning and Axis Style Control

The ability to use motion commands to program the 527 allows for easy and effective programming of this VFD in positioning applications.

While the 527 lacks the speed and accuracy of a true servo drive, it is CIP motion-ready, meaning that it can coordinate with a master clock.

This allows the 527 to serve in light-duty positioning/velocity-controlled applications.

Those seeking to coordinate motion who do not need a true servo’s full-blown benefits will find the 527 to be a cost-effective alternative.

The 527 can offer much to any machine builder or system integrator from device-level ring to safe torque.

While motion application bookending may have been the original focus, large panel builders and those who use simple positioning will see immediate benefits to the application of the PowerFlex 527.

Versatility and power are the defining qualities of a PowerFlex drive, and the 527 does not fail to deliver.

Curious about the 527?  Feel free to contact your local Power Technical Consultant to learn more.

For more information about drives and drive systems, check out the Variable Frequency Drive Main Help Page