Parker AC650G Drive Fault Codes

Troubleshoot your Parker AC650G sensorless vector drive with our updated fault code list. Learn to interpret MMI Trip messages and use DSE Lite for advanced diagnostics.

Parker AC650G Fault Codes Reference Table

Below is the complete list of trip and alarm messages. Depending on your keypad (the 4-digit 6511 or the larger 6901), the fault may appear as a shorthand code or a full text string.

650G AC Drive - Trips and Fault Messages

Fault Code and Meaning	Cause and Remedy
1 OVERVOLTAGE	Cause: The drive internal dc link voltage is too high. Remedy: The supply voltage is too high. Trying to decelerate a large inertia load too quickly; DECEL TIME too short. The brake resistor is open circuit.
2 UNDERVOLTAGE	Cause: DC link low trip. Remedy: Supply is too low/power down.
3 OVERCURRENT	Cause: The motor current being drawn from the drive is too high. Remedy: Trying to accelerate a large inertia load too quickly; ACCEL TIME too short. Trying to decelerate a large inertia load too quickly; DECEL TIME too short. Application of shock load to motor. Short circuit between motor phases. Short circuit between motor phase and earth. Motor output cables too long or too many parallel motors connected to the drive. FIXED BOOST level set too high.
4 HEATSINK	Cause: Drive heatsink temperature > 100ºC. Remedy: The ambient air temperature is too high. Poor ventilation or spacing between drives.
5 EXTERNAL TRIP	Cause: The external trip input is high. Remedy: Check configuration to identify the source of the signal (non-standard configuration).
6 INVERSE TIME	Cause: A prolonged overload condition, exceeding the Inverse Time allowance, has caused the trip. Remedy: Remove the overload condition.
7 CURRENT LOOP	Cause: A current of less than 1mA is present when 4-20mA setpoint is selected. Remedy: Look for a wire break.
8 MOTOR STALLED	Cause: The motor has stalled (not rotating). Drive in current limit >200 seconds. Remedy: Motor loading too great. FIXED BOOST level set too high.
9 ANIN FAULT	Cause: AIN2 overload on terminal 3. Remedy: Overcurrent applied in Current mode to terminal 3.
10 BRAKE RESISTOR	Cause: External dynamic brake resistor has been overloaded. Remedy: Trying to decelerate a large inertia too quickly or too often.
11 BRAKE SWITCH	Cause: Internal dynamic braking switch has been overloaded. Remedy: Trying to decelerate a large inertia too quickly or too often.
12 DISPLAY/KEYPAD	Cause: Keypad has been disconnected from drive whilst drive is running in Local Control. Remedy: Check if keypad was accidentally disconnected from drive (indicated over Comms, or by second keypad).
13 LOST COMMS	Cause: Lost communications. Remedy: COMMS TIMEOUT parameter set too short. Master device failed. Wiring broken. Incorrect Comms setup.
14 CONTACTOR FBK	Cause: Contactor feedback signal lost. Remedy: Check connection to the terminal wired to "contactor closed" parameter in Sequencing Logic.
15 SPEED FEEDBACK	Cause: Speed feedback error. Remedy: SPEED ERROR > 50.00% for 10 seconds.
16 AMBIENT TEMP	Cause: Ambient temperature issue. Remedy: The ambient temperature in the drive is too high.
17 MOTOR OVERTEMP	Cause: The motor temperature is too high. Remedy: Excessive load. Motor voltage rating incorrect. FIXED BOOST level set too high. Prolonged operation of the motor at low speed without forced cooling. Break in motor thermistor connection.
18 CURRENT LIMIT	Cause: Software overcurrent trip. If the current exceeds 180% of stack rated current for 1 second, the drive will trip. Remedy: Caused by shock loads: Remove the shock load. ACCEL TIME and/or FIXED BOOST set too high. DECEL TIME set too low.
21 LOW SPEED OVER I	Cause: The motor is drawing too much current (>100%) at zero output frequency. Remedy: FIXED BOOST level set too high.
22 10V FAULT	Cause: 10V fault detected. Remedy: +10V REF overload warning (terminal 4) - 10mA maximum.
25 DC LINK RIPPLE	Cause: The dc link ripple voltage is too high. Remedy: Check for a missing input phase.
27 OVERSPEED	Cause: Overspeed detected. Remedy: >150% base speed when in Sensorless Vector mode.
28 ANOUT FAULT	Cause: AOUT overload on terminal 5. Remedy: 10mA maximum.
29 DIGIO 1 (T9) FAULT	Cause: DIN3 overload on terminal 9. Remedy: 20mA maximum.
30 DIGIO 2 (T10) FAULT	Cause: DOUT2 overload on terminal 10. Remedy: 50mA maximum.
31 UNKNOWN	Cause: Unknown trip. Remedy: Consult technical support if persistent.
32 OTHER	Cause: "OTHER" trip is active (Trip ID 34 to 44 inclusive). Remedy: Check specific Trip ID (34-44) for details.
34 MAX SPEED LOW	Cause: During Autotune, MAX SPEED RPM limits the speed to less than the nameplate speed of the motor. Remedy: Increase the value of MAX SPEED RPM up to the nameplate rpm of the motor (as a minimum). It may be reduced, if required, after the Autotune is complete.
35 MAIN VOLTS LOW	Cause: The mains input voltage is not sufficient to carry out the Autotune. Remedy: Re-try when the mains has recovered.
36 NOT AT SPEED	Cause: The motor was unable to reach the required speed to carry out the Autotune. Remedy: Motor shaft not free to turn. The motor data is incorrect.
37 MAG CURRENT FAIL	Cause: It was not possible to find a suitable value of magnetising current to achieve the required operating condition for the motor. Remedy: Check the motor data is correct, especially nameplate rpm and motor volts. Check that the motor is correctly rated for the drive.
38 NEGATIVE SLIP F	Cause: Autotune has calculated a negative slip frequency, which is not valid. Remedy: Nameplate rpm may have been set to a value higher than the base speed of the motor. Check nameplate rpm, base frequency, and pole pairs are correct.
39 TR TOO LARGE	Cause: The calculated value of rotor time constant is too large. Remedy: Check the value of nameplate rpm.
40 TR TOO SMALL	Cause: The calculated value of rotor time constant is too small. Remedy: Check the value of nameplate rpm.
41 MAX RPM DATA ERR	Cause: MAX SPEED RPM is set to a value outside the range for which Autotune has gathered data. The drive had no data for this new operating area. Remedy: To run the motor beyond this point it is necessary to re-autotune with MAX SPEED RPM set to a higher value.
42 LEAKGE L TIMEOUT	Cause: The motor is moving during Autotune. Remedy: The motor must be stationary when starting the Autotune.
43 MOTOR TURNING ERR	Cause: The motor cannot rotate during Autotune. Remedy: The motor must be able to rotate during Autotune.
44 MOTOR STALL ERR	Cause: The leakage inductance measurement requires a test current to be inserted into the motor. It has not been possible to achieve the required level of current. Remedy: Check that the motor is wired correctly.
Product Code Error	Cause: Internal product code error detected. Remedy: Switch unit off/on. If persistent, return unit to factory.
Calibration Data Error	Cause: Internal calibration data error detected. Remedy: Switch unit off/on. If persistent, return unit to factory.
Configuration Data Error	Cause: Internal configuration data error detected. Remedy: Press the E key to accept the default configuration. If persistent, return unit to factory.

 

How to Read Parker AC650G Faults via DSE Lite

For complex troubleshooting in 2026, the local keypad may not provide enough context. Connecting your PC to the drive via the Parker Drive System Explorer Lite (DSE Lite) software allows you to look “inside” the drive logic. To do this, you will need a P3 serial port adapter located behind the removable keypad.

Key Diagnostic Features:

• Trip Log (Last 10 Events): The AC650G keeps a rolling log of the last 10 trips. Using DSE Lite, you can see if a drive has been tripping repeatedly on the same fault, which often points to a mechanical wear issue rather than an electrical failure.
• Diagnostic View: Within the software, you can monitor the “Diagnostics” menu to see real-time values of the DC Bus Voltage, Output Current, and Motor Torque at the moment the drive is running or when it trips.
• Vector Control Status: Since the 650G is a vector drive, you can use the software to monitor the Magnetizing Current and Torque Current. This is vital for diagnosing “Stall” or “Overcurrent” trips in high-load applications.

Frequently Asked Questions (FAQ)

Q: What is the difference between a 650 and a 650G?

A: The “G” variant stands for General Purpose/High Torque. It includes advanced Sensorless Vector control logic. While the fault codes are largely the same, the 650G has more specific trips related to motor modeling and torque limits.

Q: How do I reset a Parker AC650G fault?

A: Once the cause of the trip is removed, you can reset the drive by:

1. Pressing the red STOP/RESET button on the keypad.
2. Activating a digital input programmed for “Trip Reset” (usually DIN3 or DIN4).
3. Powering the drive off for 30 seconds and then back on.

Q: Why does my drive show “STACK ERROR”?

A: A “Stack Error” is a critical internal hardware or software timing fault. This usually occurs due to excessive electrical noise (EMI) or a failing control board. Ensure your motor cables are shielded and the drive is properly grounded.

Q: Can I use the 6901 Keypad to see full text faults?

A: Yes. If you upgrade from the standard 6511 (LED) keypad to the 6901 (LCD) keypad, the drive will display full English text for trips (e.g., “OVERVOLTAGE”) instead of the 4-digit codes.