How-To Guide  ·  Allen-Bradley PowerFlex 525  ·  Fault Codes & Troubleshooting

PowerFlex 525 Fault Codes: Full Reference, Causes, and Corrective Actions

Part Number: 25B-D2P3N104  ·  Bulletin 25A series B / 25B · F000–F127 Fault Reference · Source: 520-UM001

1. How the PowerFlex 525 Handles Faults

A fault is a condition that stops the drive. The condition or state of the PowerFlex 520-series drive is constantly monitored, and any change is indicated through the integral LCD display. When a fault occurs, the display provides visual notification by showing a flashing fault number and a flashing fault indicator (LED). Press the Esc key to regain control of the display.

The PowerFlex 520-series classifies every fault into one of two types. Knowing the type tells you immediately whether the drive can clear and restart itself, or whether you must physically correct the cause before the fault will clear.

2. How to Read & Clear a Fault from the Keypad

When the drive is indicating a fault, the integral LCD display flashes the fault number and the fault LED. The procedure below (from 520-UM001) acknowledges the fault, lets you review what happened, and then clears it once the cause is corrected.

Manually Clearing a Fault

1. Press Esc to acknowledge the fault. The fault information is removed so that you can use the integral keypad. Access b007 [Fault 1 Code] to view the most recent fault information.
2. Address the condition that caused the fault. The cause must be corrected before the fault can be cleared. See the full Fault Code Reference table below.
3. After corrective action has been taken, clear the fault by one of these methods: press Stop if P045 [Stop Mode] is set to a value between “0” and “3”; or cycle drive power; or set A551 [Fault Clear] to 1 “Reset Fault” or 2 “Clear Buffer”; or cycle a digital input if t062, t063, t065…t068 [DigIn TermBlk xx] is set to 13 “Clear Fault”.

A551 [Fault Clear] requires the drive to be stopped before changing this parameter.

3. Auto Restart (Reset / Run)

The Auto Restart feature provides the ability for the drive to automatically perform a fault reset followed by a start attempt without user or application intervention, allowing remote or “unattended” operation. Only certain faults are allowed to be reset. Certain faults (Type 2) that indicate possible drive component malfunction are not resettable.

If a Type 1 fault cannot be cleared within the programmed number of A541 [Auto Rstrt Tries], the drive declares fault F033 [Auto Rstrt Tries] and must be cleared manually.

4. Complete Fault Code Reference (F000–F127)

The table below is the complete Fault Types, Descriptions, and Actions listing from Rockwell publication 520-UM001 (pages 161–163). The Type column is the fault class: 1 = Auto-Reset/Run, 2 = Non-Resettable. Where Rockwell lists multiple corrective actions, all are shown.

(1) See Fault Types (Section 1). (2) Fault F013 may be cleared by the auto-restart routine and is attempted only once; it ignores the value set in parameter A541 [Auto Rstrt Tries]. (3) Faults F015, F059, F073, F083, F091, and F111 are not applicable to PowerFlex 523 drives.

5. Common Faults: Deep Dive

A handful of fault codes account for the majority of PowerFlex 525 trips in the field. Here is what each one is telling you, drawn directly from the Rockwell descriptions above.

F004 UnderVoltage (Type 1)

The DC bus voltage fell below the minimum value. Monitor the incoming AC line for low voltage or a line power interruption. Because it is a Type 1 fault, it can be auto-cleared (with or without restart) via A541/A542 — useful on sites with brown-outs or brief power dips.

F005 OverVoltage (Type 1)

The DC bus voltage exceeded the maximum value. Monitor the AC line for high line voltage or transient conditions. Bus overvoltage can also be caused by motor regeneration — a load that drives the motor (high-inertia or overhauling loads) on a fast decel. Extend the decel time or install the dynamic brake option to absorb the regenerated energy.

F013 Ground Fault (Type 1)

A current path to earth ground has been detected at one or more of the drive output terminals. Check the motor and external wiring to the drive output terminals for a grounded condition. Note that this fault may be cleared by the auto-restart routine only once, regardless of the A541 [Auto Rstrt Tries] value.

F021 Output Phase Loss (Type 1)

Output Phase Loss, detected only when enabled via A557 [Out Phas Loss En]. Verify the motor wiring and verify the motor itself. A loose output lead or a failed motor winding are the usual culprits.

F029 Analog In Loss (Type 1)

An analog input is configured to fault on signal loss, and a signal loss has occurred. This behavior is configured with t094 [Anlg In V Loss] or t097 [Anlg In mA Loss]. Check for broken or loose connections at the inputs, and check the relevant parameters. Common on 4–20 mA setpoint loops when a sensor or cable opens.

F070 Power Unit (Type 2)

A failure has been detected in the drive power section. First check that the maximum ambient temperature has not been exceeded, then cycle power. If the fault cannot be cleared, replace the drive — this is a non-resettable (Type 2) hardware fault.

6. Fault History & Diagnostics

The PowerFlex 520-series stores a rolling history of the most recent faults so you can diagnose intermittent or unattended trips after the fact. The three most-recent fault codes are available right on the keypad, and the full Fault and Diagnostic Group captures a 10-deep buffer with a time stamp and a snapshot of drive conditions at each fault.

Keypad Fault Codes (b007–b009)

Codes appear in these parameters in the order that they occur (b007 [Fault 1 Code] = the most recent fault). Repetitive faults are only recorded once.

Full Fault Buffer (F604–F660, PowerFlex 525)

The Fault and Diagnostic Group extends the history to 10 faults deep and records the operating conditions captured at the instant of each fault — the single most useful data set when chasing an intermittent trip.

7. When to Replace vs. Repair

The fault type is your first decision point. Type 1 (Auto-Reset/Run) faults are almost always environmental or load-related — line voltage, ambient temperature, wiring, or programming — and rarely mean the drive itself has failed. Type 2 (Non-Resettable) faults are the ones to watch: several of them, after the documented troubleshooting steps, end with Rockwell's own instruction to replace the drive or control module (both of which we stock and ship same-day) if the fault cannot be cleared.

Reference Documentation

The following Rockwell Automation publications were used as references for this guide. These are the official manufacturer documents for the hardware covered in this article.