Parker AC650 Drive Fault Codes

Troubleshoot your Parker SSD 650/650V drive with our updated fault code list. Learn to interpret MMI Trip messages, use DSE Lite via the P3 port, and minimize downtime.

Parker AC650 Fault Codes Reference Table

Below is the complete list of trip messages and warning codes. Please refer to the specific text displayed on your 6511 or 6901 keypad.

Fault Code	Cause & Solution
1 Over Voltage dCHI	The drive internal dc link voltage is too high: - 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 To help prevent this trip, enable the DC Link Volts Limit feature Internal dc link voltage has reached midway between the over voltage trip level and the dynamic braking resistor control voltage.
2 Under Voltage dCLO	DC link low trip: - Supply is too low/power down Internal dc link voltage has reached midway between the lowest expected instantaneous voltage and the undervoltage trip level.
3 OC Over Current	The motor current being drawn from the drive is too high: - Trying to accelerate a large inertia load too quickly; ACCEL TIME time too short - Trying to decelerate a large inertia load too quickly; DECEL TIME 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 The over current trip uses a multiple-attempt strategy. The warning is triggered if two or more consecutive overcurrent events are encountered (whereas five consecutive events are required for a Trip to occur).
HOt 4 HEATSINK	Drive heatsink temperature > 100ºC: - The ambient air temperature is too high Poor ventilation or spacing between drives.
5 Et EXTERNAL TRIP	The external trip input is high: - Check configuration to identify the source of the signal (non-standard configuration).
It 6 INVERSE TIME	A prolonged overload condition, exceeding the Inverse Time allowance, has caused the trip: - Remove the overload condition
LOOP 7 CURRENT LOOP	A current of less than 1mA is present when 4-20mA setpoint is selected: - Look for a wire break.
8 StLL MOTOR STALLED	The motor has stalled (not rotating) Drive in current limit >200 seconds: - Motor loading too great. - FIXED BOOST level set too high.
9 t3 ANIN FAULT	AIN2 overload on terminal 3: - Overcurrent applied in Current mode to terminal 3.
12 dISP DISPLAY KEYPAD	Keypad has been disconnected from drive whilst drive is running in Local Control: - Keypad accidentally disconnected from drive (indicated over Comms, or by second keypad).
13 SCI / SC1 LOST COMMS	Lost communications: - COMMS TIMEOUT parameter set too short - Master device failed - Wiring broken - Incorrect Comms setup
14 CnTC CONTACTOR FBK	Contactor feedback signal lost: - Check connection to the terminal wired to "contactor closed" parameter in Sequencing Logic (non-standard configuration).
17 Ot 17 MOTOR OVERTEMP	The motor temperature is too high: - 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 IHI / 1H1 CURRENT LIMIT	Software overcurrent trip: - If the current exceeds 180% of stack rated current for a period of 1 second, the drive will trip. This is caused by shock loads. Remove the shock load. - ACCEL TIME and/or FIXED BOOSTset too high - DECEL TIME set too low
21 LSPD LOW SPEED OVER I	The motor is drawing too much current (>100%) at zero output frequency: - FIXED BOOST level set too high.
22 t4 10V FAULT	10V fault: - +10V REF overload warning (terminal 4) - 10mA maximum.
24 ShTt / Shft DESATURATION	Desaturation: - Instantaneous overcurrent. Refer to OVERCURRENT in this table.
25 DCTP DC LINK RIPPLE	The dc link ripple voltage is too high: - Check for a missing input phase.
26 dbSC BRAKE SHORT CCT	Brake resistor overcurrent: - Check brake resistor value is greater than minimum allowed.
28 t5 ANOUT FAULT	AOUT overload on terminal 5: - 10mA maximum.
29 t9 DIGIO 1 (T9) FAULT	DIN3 overload on terminal 9: - 20mA maximum.
30 t10 DIGIO 2 (T10) FAULT	DOUT2 overload on terminal 10: - 50mA maximum.
31 tTIP UNKNOWN	Unknown trip
33 ICAL	Zero I Current Calibration: - Current sensor calibration fault. Switch unit off/on. If persistent, return to factory.
CODE	Product Code Error Switch unit off/on. - If persistent, return unit to factory
CAL Calibration Data Error	Switch unit off/on. - If persistent, return unit to factory
dAtA Configuration Data	Error Press "E" the key to accept the default configuration. - If persistent, return unit to factory

How to Read Parker AC650 Faults via DSE Lite

While the clip-on keypad provides immediate feedback, connecting your PC to the drive using the Parker Drive System Explorer Lite (DSE Lite) software yields the most accurate diagnostic data for 2026. Note that the AC650 requires a specific serial interface cable (P3 port adapter) to connect to a PC.

Key Diagnostic Features:

• Trip History: The AC650 stores a history of the last 10 trips. By connecting via DSE Lite, you can view the “Trips History” parameter to identify recurring issues that may have happened during previous shifts.
• Real-Time Monitoring: DSE Lite allows you to view the drive’s block diagram in real-time. You can monitor the “Sequencing Logic” to see exactly which input or internal logic block is triggering the stop command.
• P3 Port Connection: The diagnostics port is located behind the keypad. Using the official Parker USB-to-Serial programming lead allows you to extract parameters and diagnostic logs even if the keypad display is damaged.

Frequently Asked Questions (FAQ)

Q: What is the difference between an Alarm and a Trip?

A:

• Alarms (Alerts): These indicate a condition that is nearing a limit (e.g., “Motor Over Temp” warning) but allows the drive to keep running. The display may flash.
• Trips: These are critical faults (e.g., “OVER VOLTS” or “OVER I”) where the drive immediately cuts power to the motor and coasts to a stop.

Q: How do I reset a Parker AC650 fault?

A: Once the fault condition is resolved, you can reset the drive by:

1. Pressing the red STOP/RESET button on the keypad.
2. Toggling a Digital Input (often DIN3 or DIN4 depending on the macro configuration) assigned to “Remote Trip Reset.”
3. Cycling the main power (Wait for the display to go blank before repowering).

Q: What does “DC LINK RIPPLE” mean?

A: This is a common fault on older 650 units. It usually indicates a missing input phase (single-phasing) or an imbalance in the incoming AC power supply. Check your fuses and incoming voltage lines.