This chapter provides a comprehensive guide for troubleshooting PowerFlex 750-Series faults, alarms, and configurable conditions, ensuring efficient and effective maintenance.

PowerFlex 755 Drive Troubleshooting Summary:

Faults and Alarms:

    Faults: Categorized into three types: Auto Reset Run, Resettable, and Non-Resettable.
    Alarms: Divided into two types: Type 1 (user-configurable) and Type 2 (non-configurable and prevents drive start).
    Configurable Conditions: Can be set by the user as an alarm or fault.

Troubleshooting and Maintenance:

    Fault Display: Automatically appears in case of a fault, showing the fault code, description, and elapsed time.
    Clearing Faults: After acknowledging and addressing the cause, faults can be cleared via the HIM or by power cycling.

Additional Information:

    Fault and Alarm Codes: Displayed in formats varying with the port and event number, ensuring precise identification.
    Hardware Service Manual and System Resource Allocation: Provide guidance for maintenance and managing system resources.

Refer to the relevant sections of the user manual for detailed information and procedures.

27- Torq Prove Cflct: Alarm 2 is activated when P1100 [Trq Prove Cfg] is enabled. It requires proper setting of P35 [Motor Ctrl Mode], P125 [Pri Vel Fdbk Sel], and P135 [Mtr Psn Fdbk Sel]. If these parameters are set to a feedback module, the module parameters also need correct configuration.

28- TP Encls Config: Alarm 2 signifies that Encoderless TorqProve is enabled, but the user hasn't comprehended the concerns of encoderless operation. It's advised to refer to the “Attention” note on page 367 related to using TorqProve without an encoder.

29- Analog In Loss: A configurable fault that indicates a lost signal in the analog input.

33- AuRsts Exhausted: This resettable fault is activated when the drive fails to reset a fault and restart after a certain number of attempts.

36- SW OverCurrent: A resettable fault triggered when the drive output current surpasses its 1 ms current rating, typically between 200-250% of the drive's continuous rating.

 38,39,40- Phase to Ground Faults: Several resettable faults, namely Phase U to Grnd, Phase V to Grnd, Phase W to Grnd, Phase UNegToGrnd, Phase VNegToGrnd, and Phase WNegToGrnd, are activated when a phase to ground fault is detected between the drive and motor.

41,42,43,44,45,46- Phase Short Faults: Resettable faults like Phase UV Short, Phase VW Short, and Phase WU Short are triggered when excessive current is detected between specific output terminals.

48- System Defaulted: This resettable fault indicates that the drive was instructed to write default values.

49- Drive Powerup: Marks a power-up event in the Fault Queue, indicating the drive has been power cycled.

51-Clr Fault Queue: Indicates that the fault queue has been cleared.

55- Ctrl Bd Overtemp: A resettable fault that signals that the main control board's temperature sensor detected excessive heat.

58- Module Defaulted: This resettable fault is activated when the module is commanded to write default values.

59- Invalid Code: A resettable fault indicating an internal error.

61- Shear Pin 1: This configurable fault is activated when the programmed value in P436 [Shear Pin1 Level] is surpassed.

62-Shear Pin 2: A similar configurable fault, it is triggered when the value set in P439 [Shear Pin2 Level] is exceeded.

64- Drive OverLoad: This issue can manifest in two ways. As an Alarm 1, it is activated when P940 [Drive OL Count] exceeds 50% but remains below 100%. As a Resettable Fault, the drive will coast if P940 [Drive OL Count] surpasses 100%. It's advised to lessen the mechanical load on the drive. The fault can also be triggered if there's no detection of the inverter fiber optic connection on a Frame 8 drive upon power up.

67- Pump Off: Alarm 1 indicates that a Pump Off condition has been detected.

71,72,73,74,75,76 - Port Adapter Faults: Faults from Port 1 Adapter to Port 6 Adapter are resettable faults that indicate issues with the DPI communications option for their respective ports. The specific event can be seen in the device event queue.

77- IR Volts Range: This fault can be triggered in two scenarios. As Alarm 2, it's activated when the default for P70 [Autotune] is set to “Calculate” and the calculated value for P73 [IR Voltage Drop] is outside the acceptable range. As a Resettable Fault, if P70 [Autotune] is set to “Static Tune” or “Rotate Tune”, and the measured value for P73 [IR Voltage Drop] during the Autotune procedure is outside of acceptable values.

78- FluxAmpsRef Rang: Similar to the previous fault, Alarm 2 is activated when the default for P70 [Autotune] is “Calculate” and the value for flux amps determined by the Autotune procedure exceeds P26 [Motor NP Amps]. As a Resettable Fault, if P70 [Autotune] is set to “Static Tune” or “Rotate Tune” and the measured value for flux amps during Autotune exceeds P26 [Motor NP Amps].

79- Excessive Load: A resettable fault indicating that the motor didn't achieve the required speed in the time allotted during Autotune.

80- AutoTune Aborted: This resettable fault is activated either when the Autotune function is manually canceled or a fault is detected.

81,82,83,84,85,86 - DPI Loss Faults: Faults from Port 1 DPI Loss to Port 6 DPI Loss are resettable faults indicating that the respective DPI port has stopped communicating. It's suggested to check connections and ensure proper drive grounding.


87- IXo VoltageRange: As Alarm 2, this is activated when the default for P70 [Autotune] is “Calculate” and the voltage computed for motor inductive impedance goes beyond 25% of P25 [Motor NP Volts]. As a Resettable Fault, it triggers when P70 [Autotune] is set to “Static Tune” or “Rotate Tune” and the measured voltage for the motor's inductive impedance exceeds 25% of P25 [Motor NP Volts].

91- Pri VelFdbk Loss: This configurable fault indicates that there has been a Feedback Loss for the source of P134 [Aux Vel Feedback]. The issue might be due to a problem detected by the feedback option module determined by P125 [Pri Vel Fdbk Sel] or a communication loss between the feedback option module and the main control board.

- PowerFlex 755 fault codes >>

- PowerFlex 755 fault codes 2 >>

- PowerFlex 755 fault codes 3 >>

- PowerFlex 755 fault codes 4 >>

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