How to solve Error Code 24

How to solve Error Code 24

Fault code:

【24】The voltage imbalance fault of positive and negative busbars

Reason:

hardware failure

Capacitor aging or damage: Equipment that has been in use for more than 3 years should be carefully inspected for capacitor bulging or leakage. Aging can lead to a decrease in filtering ability and cause voltage fluctuations.  ‌

IGBT module abnormality: By detecting switch waveform distortion with an oscilloscope, the fault can be confirmed. Damage to a certain phase can cause voltage abnormalities.  ‌

Loose or oxidized wiring: Loose terminals or oxidized cables can increase contact resistance and cause voltage deviation.  ‌

Input side issues

Parallel imbalance of battery pack: When a certain group of batteries has insufficient power or high internal resistance, the corresponding phase voltage may be 20% -30% lower.  ‌

Uneven power generation of photovoltaic panels: obstruction, aging, or wiring errors can cause a difference of over 50% in output power between a single group, lowering the overall voltage.  ‌

Abnormal control logic

Sampling circuit fault: Open circuit in the detection line or sensor failure can cause the controller to misjudge the voltage value.  ‌

Defects in voltage equalization algorithm: If the algorithm is not optimized for multi-level inverters, the phase voltage deviation may exceed 10%.  ‌

Solution:

Preliminary judgment: Lock the fault direction through inverter alarm codes (such as DC undervoltage/AC overvoltage) and measure the grid voltage reference value.  ‌

DC side detection: measure the open circuit voltage of the string, and check for component obstruction or aging when it is below 100V; Check for loose and oxidized MC4 connectors.  ‌

Communication side analysis: detecting line impedance, upgrading cables to 6mm ² or more for long-distance transmission; Confirm the status of the reactive power compensation device.  ‌

Control module verification: Check the contact of the sampling channel and the aging of the drive line on the main control board; Calibrate the pressure equalization algorithm to ensure a deviation of ≤ 5%.  ‌

Note: Please do not dismantle the machine without permission, otherwise it will be out of the warranty of Ktech.