Finding the Right Allen-Bradley PowerFlex 525 Drive

What the PowerFlex 525 Is, and Where It Fits

The PowerFlex 525 is Allen-Bradley’s current-generation entry-level VFD. It’s part of the PowerFlex 520-series, which Rockwell positions as the compact, general-purpose drive line, distinct from the larger PowerFlex 750-series (753, 755, 755T) for higher-horsepower industrial applications.

Within the 520-series, there are actually three different drives that share a common modular hardware platform but differ in capability:

• PowerFlex 523 (Bulletin 25A) is the cost-optimized version. No embedded EtherNet/IP and no Safe Torque Off. Best for standalone machines that don’t need network connectivity or built-in functional safety.
• PowerFlex 525 (Bulletin 25B) is the workhorse covered in this guide. Embedded EtherNet/IP, Safe Torque Off as standard, USB programming, and broad motor-control support. The default choice for most applications under 30 HP.
• PowerFlex 527 (Bulletin 25C) is the integrated-motion variant designed to work tightly with Logix controllers in coordinated motion applications. Niche use case; most general-purpose buyers don’t need it.

The 525’s positioning is straightforward: it’s the right drive for compact, general-purpose AC motor control up to 30 HP, in applications that benefit from EtherNet/IP connectivity, built-in safety, and integration with the broader Allen-Bradley control architecture. If your motor is bigger than 30 HP, or your application needs advanced process control, regenerative braking, or coordinated motion at scale, the 750-series is where you’ll want to look. If you don’t need EtherNet/IP or built-in STO and you’re looking to save cost, the 523 is the sibling to consider.

A few practical features worth knowing about the 525 before diving into the catalog:

• Modular design. The 525 separates into a power module and a control module, which is more than a cosmetic detail. It means a failed control module can be replaced without taking the power module out of the panel, and the same power module can be paired with different control modules for different applications. This is one of the design choices that makes the 525 easier to maintain than the older PowerFlex 40 it replaced.
• Embedded EtherNet/IP. Built into every 525, no separate communication card needed for Ethernet. Optional communication cards (DeviceNet, PROFIBUS, etc.) plug into the control module if you need a different network.
• Safe Torque Off (STO). Standard on every 525. This is functional safety that meets ISO 13849-1 PLd / SIL 2 and removes rotational power without removing drive power. We’ll come back to STO in the migration section because it’s the single most common gotcha when moving from PowerFlex 40.
• Voltage range. The 525 covers 100-120V, 200-240V, and 380-480V supplies, with single-phase and three-phase variants. There’s also a 525V-690V (~480-600V class) variant. The full catalog spans these voltage classes and gets laid out in section 2.

The PowerFlex 525 Catalog: HP, Voltage, and Configuration

Every PowerFlex 525 catalog number tells you the drive’s voltage class, input phase, horsepower (via the current rating), and whether it includes an EMC filter. Once you know which voltage and motor size you need, the right catalog number falls out of the table.

The 525 lineup covers five voltage classes: 100-120V single-phase, 200-240V single-phase, 200-240V three-phase, 380-480V three-phase, and 525-600V three-phase. Inside each class, drives are offered by horsepower rating, and the 200-240V single-phase and 380-480V classes are also available in both unfiltered (no EMC filter, code N104) and filtered (with EMC filter, code N114) versions.

100-120V single-phase input (0-230V three-phase output)

Compact drives for fractional-HP applications running off standard single-phase line power.

200-240V single-phase input (0-230V three-phase output)

For single-phase 240V applications, available unfiltered (N104) or with integrated EMC filter (N114).

200-240V three-phase input (0-230V three-phase output)

380-480V three-phase input (0-460V three-phase output)

The most common voltage class in North American industrial applications. Available unfiltered (N104) up to 20 HP, and with integrated EMC filter (N114) across the full range up to 30 HP.

Note: The 25 HP and 30 HP ratings are only available with the integrated EMC filter; there’s no unfiltered version of those two sizes.

525-600V three-phase input (0-575V three-phase output)

For 600V applications, common in Canadian industrial systems and some North American applications.

Reading the columns

• ND vs HD (Normal Duty vs Heavy Duty) matters above 15 HP. Normal duty assumes a typical industrial load with 110% overload capability for 60 seconds. Heavy duty assumes higher overload requirements (150% for 60 seconds, 180% for 3 seconds) and derates the HP rating for the same physical drive. Below 15 HP, ND and HD are identical.
• Frame size (A through E) determines the physical dimensions and weight of the drive, which drives panel design and DIN-rail vs panel-mount decisions. Frame A is the smallest at ~1.1 kg; Frame E is the largest at ~12.9 kg.
• N104 vs N114 is the EMC filter code: 0 means no integrated filter (use external filtering if you need to meet EMC requirements), 1 means integrated filter. For applications subject to EN61800-3 Category C2 or C3 EMC requirements, the filtered version saves the cost and panel space of an external filter.

If you know your voltage class, motor HP, and whether you need EMC filtering, the catalog number is determined. If you’re not sure which row matches your application, send us the motor nameplate and we’ll spec it for you.

How to Read a PowerFlex 525 Catalog Number

The catalog number on a PowerFlex 525 drive isn’t random; it’s a position-coded summary of the drive’s voltage, horsepower rating, enclosure, and configuration. Once you know what each position means, you can read the drive’s specs straight off the label.

A standard 525 catalog number template maps contextually to: 25B – D 013 N 1 1 4. Each position has a specific meaning:

So a 25B-D013N114 decodes as:

• 25B → PowerFlex 525
• D → 480V three-phase input
• 013 → 13 A output (7.5 HP / 5.5 kW)
• N → IP20 / NEMA Open enclosure
• 1 → Standard interface
• 1 → Integrated EMC filter
• 4 → Standard braking

In plain English: a PowerFlex 525, 480V three-phase, 7.5 HP, open enclosure, with EMC filter and standard braking. A few notes on reading the current code, which is the trickiest part:

• The “P” represents a decimal point. A “2P5” means 2.5 amps, “6P0” means 6.0 amps, “1P4” means 1.4 amps. Once the current rating reaches 10 amps or higher, the code becomes a straight three-digit number (010 = 10.5 A, 013 = 13 A, 030 = 30 A). The current code, combined with the voltage class, determines the HP rating; the tables in section 2 show the exact mapping.
• The final three positions (interface, EMC filter, braking) are nearly always “1,” “0 or 1,” and “4.” The “1” interface and “4” braking codes are standard across the line; only the EMC filter position varies meaningfully between N104 (no filter) and N114 (filter).

If you have a drive label in front of you, this is enough to decode it on sight. If you have only partial information (a motor nameplate, a system spec sheet), the tables in section 2 work in reverse: find your voltage and HP, read off the catalog number.

Migrating from PowerFlex 40 (Bulletin 22B) to PowerFlex 525 (Bulletin 25B)

The PowerFlex 40 is discontinued. If you’re maintaining a plant that runs 22B drives, you have two paths: source remaining PowerFlex 40 inventory through the secondary market to keep your existing system unchanged, or migrate to the PowerFlex 525, which is Rockwell’s official engineered replacement. Both are valid, and the right call depends on your timeline, your appetite for change, and how many drives you’re maintaining.

The catalog number translation is genuinely clean

Rockwell designed the 525 as a direct replacement for the 40, and the catalog numbering reflects that. For most ratings, the migration is as simple as swapping the 22B bulletin prefix for 25B, keeping the voltage letter (V, A, B, D, or E), current code (2P5, 010, 030, etc.), and configuration suffix the same.

A few examples:

The voltage letters (V, A, B, D, E), current codes, enclosure codes (N), interface (1), EMC filter (0 or 1), and braking (4) all carry over identically. For most 22B catalog numbers, finding the 25B equivalent is a one-character change.

The 525 also extends the range beyond what the 40 offered. The 40 topped out at 20 HP at 480V; the 525 adds 25 HP and 30 HP ratings (25B-D037N114 and 25B-D043N114). If you’re upgrading and want headroom you didn’t have before, those higher ratings are an option that didn’t exist on the 22B.

What changes during the migration

The catalog mapping is clean, but the migration itself is not literally drop-in. Five operational elements are worth planning for:

• Safe Torque Off (STO) wiring is required. This is the single most common surprise. The PowerFlex 525 has Safe Torque Off as a standard built-in feature, and the drive will not run unless the STO inputs are wired. If you’re not actually using the safety function, you have to install jumper wires (+24V to STO Input 1 and STO Input 2, with STO Common to Digital Common) before the drive will start. Skip this step and the drive faults out with Fault F002 (Auxiliary Input). The PowerFlex 40 had no STO, so this is brand-new on the 525 and catches first-time migrators every time.
• Embedded EtherNet/IP changes your network plan. The 525 has EtherNet/IP built in, while the 40 needed an external 22-COMM-E adapter card for Ethernet. If your existing 40 is on EtherNet/IP via a 22-COMM-E, you can retire that card and connect the 525’s onboard port directly. If your existing 40 is on a different network (DeviceNet, PROFIBUS, etc.), you’ll need the equivalent 25-COMM-D or 25-COMM-P adapter for the 525.
• Parameter numbers and structure changed. Programs don’t transfer one-to-one. The 525 uses a different parameter numbering scheme than the 40, and Rockwell provides a name-by-name parameter cross-reference in the official migration guide (publication PFLEX-AP011). You’ll need to re-enter your settings rather than copy them over, or using DriveExecutive / Connected Components Workbench to push a saved configuration to the new drive.

A few smaller items that round out the change list: the 525’s control terminal layout differs slightly from the 40’s (the terminal numbering is similar but check the wiring diagram before reconnecting), the 525 has more digital and analog I/O than the 40 (seven digital inputs vs. five, two analog inputs vs. one), and the 525’s frame sizes are similar but not identical to the 40’s, so verify panel-mounting clearances.

If you’d rather not migrate, PowerFlex 40 drives remain widely available as of 2026. Many plants choose to source 22B drives to keep an existing system unchanged, especially when the program is complex, the network setup is tightly integrated, or a planned migration is on the calendar but not immediate. Send us your 22B catalog number and we’ll confirm what’s available.

Common PowerFlex 525 Accessories

The PowerFlex 525 supports a range of optional accessories that plug into the control module’s two accessory slots or attach externally. The most common ones are listed below. All of these are real recurring searches when a 525 needs to be expanded or repaired.

A few notes worth knowing when ordering accessories:

• The 25B accepts two accessory cards simultaneously. The 525 has two slots; you can run a communication card and an encoder card at the same time, for example. The 523 has only one slot.
• The 525’s embedded EtherNet/IP port is separate from the 25-COMM-E2P. You don’t need the E2P card just to get Ethernet; the embedded single-port is included on every 525. You only need the E2P if you want dual-port DLR for ring topology.
• The 25B-CTM1 is the field-replaceable control module. Because the 525 is modular (power module and control module separable), a failed control module can be replaced without changing the power module or pulling the drive from the panel. This is one of the practical maintenance advantages over the older PowerFlex 40.

If you’re not sure which accessory fits your drive, send us your 25B catalog number and the function you’re trying to add. Whether you’re speccing a new PowerFlex 525, replacing a failed 25B drive, or upgrading from a discontinued PowerFlex 40, the starting point is the same: knowing the exact catalog number you need and confirming it’s actually available.

TCI Supply is an unauthorized distributor of Allen-Bradley.

Companion Hardware Sourcing Guides

Building or modifying a manufacturing line requires coordination across your variable frequency drives, backbone enclosures, controller capabilities, and physical terminations. Review our companion hardware guides to map your complete hardware profile:

• Processor Sizing: Read our 1756 ControlLogix Processor Replacement Guide to evaluate memory capacities and CPU generations across backplanes.
• Chassis Networking Bridges: Visit our 1756 ControlLogix Communication Module Guide to coordinate EtherNet/IP distributed routing architectures and ControlNet loops.
• Field Wiring & Signal Cards: Visit our 1756 ControlLogix I/O Module Guide to total up power bus current constraints across discrete and analog signal racks.
• Backplane Power & Chassis Enclosures: Visit our 1756 ControlLogix Chassis and Power Supply Sourcing Guide to size backbone enclosures and backplane power constraints.
• High-Power AC Drives: Visit our Allen-Bradley PowerFlex 753 and 755 Sourcing Guide to spec mid-tier and high-power industrial induction control.

Frequently Asked Questions