Quick answer
A PowerFlex 4 or 40 that faults stops the motor and its keypad flashes the fault number and the fault indicator; the manuals write the number as F and a number, for example F4. Read the code, find it in the table below, fix the cause, then clear it with the Stop key, a power cycle or A100 [Fault Clear]. Type 1 faults may reset by themselves if auto restart is set up; Type 2 faults need the cause fixed before they clear.
Jump to a code:
Safety first: lock out and tag out the drive and the machine before you open the drive or touch the wiring, and follow Rockwell Automation's procedure in the manual. The drive's DC bus capacitors stay charged after power is removed: both manuals say to wait 3 minutes, and the PowerFlex 40 manual adds that DC– to DC+ on the power terminal block must read zero: a qualified person verifies zero voltage with a properly rated meter, checking the meter on a known source before and after – a dark display doesn't mean it's safe. Never bypass a safety circuit or switch off a fault to keep a machine running. Only qualified personnel should work on drives, and any measurement on energized equipment follows your site's live-work and arc-flash rules.
Reading and clearing a PowerFlex 4 / 40 fault
- Note the code. Press Esc to acknowledge the fault so you can use the keypad. d007 [Fault 1 Code] holds the latest fault, d008 and d009 the two before it; a repeating fault is recorded once.
- Look it up in the table below or in the manual, and fix the cause first – a fault whose cause is still there comes straight back.
- Clear it: press Stop (when P037 [Stop Mode] is set from 0 to 3), cycle power, set A100 [Fault Clear] to 1 “Reset Fault”, or cycle a digital input set to 7 “Clear Fault” (A051 to A052 on a PowerFlex 4, A051 to A054 on a PowerFlex 40).
- Watch the restart. If the same code returns, go back through the checks before resetting again.
The PowerFlex 4 and PowerFlex 40 manuals use the same fault numbers, names and types. F29 and F80 appear only in the PowerFlex 40 manual (marked “PowerFlex 40 only”), and F3 Power Loss is described differently in each.
PowerFlex 4 / 40 fault codes
This table lists every code in the two manuals' fault tables, in short form. The manuals have the full corrective actions.
| Code | What it means | Likely causes | First checks |
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| F2Auxiliary InputType 1 | The auxiliary input interlock is open. |
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| F3Power LossType 2 | PowerFlex 4: the DC bus stayed below 85% of nominal. PowerFlex 40: the DC bus ripple got too high. |
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| F4UnderVoltageType 1 | The DC bus voltage fell below the drive's minimum. |
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| F5OverVoltageType 1 | The DC bus voltage went above the drive's maximum. |
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| F6Motor StalledType 1 | The drive could not accelerate the motor. |
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| F7Motor OverloadType 1 | The drive's electronic motor overload protection tripped. |
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| F8Heatsink OvrTmpType 1 | The heatsink temperature went above a preset limit. |
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| F12HW OverCurrentType 2 | Output current went past the drive's hardware current limit. |
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| F13Ground FaultType 2 | The drive found a current path to earth ground on one or more output terminals. |
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| F29Analog Input LossType 1PowerFlex 40 only | An analog input set to fault on signal loss lost its signal. |
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| F33Auto Rstrt TriesType 2 | The drive used up its programmed auto-restart attempts (A092 [Auto Rstrt Tries]) without clearing the fault. |
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| F38 / F39 / F40Phase U to GndType 2 | A phase-to-ground fault was found between the drive and the motor on that phase (U, V or W). |
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| F41 / F42 / F43Phase UV ShortType 2 | Excessive current was found between two output terminals (U-V, U-W or V-W). |
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| F48Params Defaulted | The drive was told to write its factory default settings. |
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| F63SW OverCurrentType 1 | Output current went above the programmed A098 [SW Current Trip]. |
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| F64Drive OverloadType 2 | The drive's own rating (150% for 1 minute or 200% for 3 seconds) was exceeded. |
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| F70Power UnitType 2 | The drive detected a failure in its power section. |
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| F71Net Loss | The communication network has faulted. |
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| F80SVC AutotunePowerFlex 40 only | The autotune was canceled or failed. |
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| F81Comm LossType 2 | The RS-485 (DSI) port stopped communicating. |
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| F100Parameter ChecksumType 2 | The drive's stored parameter checksum does not match. |
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| F122I/O Board FailType 2 | A failure was detected in the drive's control and I/O section. |
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The fault name is the short text the drive shows.
Sources: Rockwell Automation, PowerFlex 4 Adjustable Frequency AC Drive User Manual (firmware revision 7.xxx), publication 22A-UM001L-EN-E (September 2024) – Chapter 4, Troubleshooting: Fault Types, Descriptions, and Actions (Table 12); Rockwell Automation, PowerFlex 40 Adjustable Frequency AC Drive User Manual (firmware revision 1.xx to 7.xx), publication 22B-UM001J-EN-E (September 2025) – Chapter 4, Troubleshooting: Fault Types, Descriptions, and Actions (Table 10), read on October 17, 2026.
Meanings, causes and checks are summarized in our own words. The manuals are the reference: they have every code, the full corrective actions and the safety instructions. A newer revision of a manual may add codes, so check the current revision for your drive.
PowerFlex 4 / 40 AC drives in stock
PowerFlex 4 (22A) and PowerFlex 40 (22B) part numbers on our shelves right now. Every item is photographed, so check the nameplate – catalog number and series – against the drive you're replacing.
- 22A-D6P0N104Allen Bradley 22A-D6P0N104 SER A 3 Phase, 380-480V,48-63Hz
- 22B-D2P3C104Allen-Bradley PowerFlex 40 22B-D2P3C104 AC Drive 1HP 0.75kW 480V 3PH NEMA 4X VFD
- 22A-A8P0N104Allen Bradley 22A-A8P0N104 Series A 48-63HZ
- 22A-D1P4N104Allen-Bradley PowerFlex 4 22A-D1P4N104 AC Drive VFD 0.5HP 1.4A 480V 3-Phase
- 22B-D2P3N104Allen-Bradley 22B-D2P3N104 Ser A PowerFlex 40 AC Drive VFD 1HP 0.75kW 3-Phase
Fault won't clear?
When the checks point to the drive itself – the manual's “replace the drive” or “replace the control module” – send us the fault code and the catalog number from the nameplate. We check our shelves and our sourcing network and reply with a written quote. Purchase orders are welcome; payment is due before we ship.
Frequently asked questions
How do I clear a fault on a PowerFlex 4 or PowerFlex 40?
Press Esc to acknowledge it, fix what caused it, then clear it: press Stop (when P037 [Stop Mode] is 0 to 3), cycle power, set A100 [Fault Clear] to 1, or cycle a digital input set to Clear Fault. A fault comes straight back if its cause is still there.
What is the difference between a Type 1 and a Type 2 fault?
A Type 1 fault can be reset by auto restart (A092 [Auto Rstrt Tries] and A093 [Auto Rstrt Delay]) once the condition is gone. A Type 2 fault is never auto-reset: the cause has to be fixed before it clears. With A092 above 0 and A093 at 0, an OverVoltage, UnderVoltage or Heatsink OvrTmp fault clears without a restart.
Where can I see which faults a PowerFlex 4 or 40 had?
d007 [Fault 1 Code] holds the most recent fault, d008 and d009 the two before it. A fault that repeats is recorded once.
Are the PowerFlex 4 and PowerFlex 40 fault codes the same?
Nearly: both manuals use the same numbers, names and types. The PowerFlex 40 adds F29 Analog Input Loss and F80 SVC Autotune, and its F3 Power Loss means too much DC bus ripple, not a low bus.
Can you supply a replacement PowerFlex 4 or PowerFlex 40 drive?
Send the catalog number from the nameplate and the fault code through our quote form. We check our shelves and our sourcing network and reply with a written quote.