Inverter——How to solve Error Code 40 and 43

Fault code:【40】【43】： Parallel connection fault

Reason:

Line connection error: When connected in parallel, there may be connection errors between MPPT and photovoltaic modules, batteries, or loads, such as reversed positive and negative poles, cross connection of lines, etc., which can cause current to flow abnormally.

Loose connection: Line connectors, plugs, and other parts may become loose after long-term use or vibration, increasing contact resistance and causing problems such as heating and ignition, affecting the normal operation of MPPT.

Differences in photovoltaic module parameters: The photovoltaic modules connected to parallel MPPT have significant differences in parameters such as open circuit voltage, short-circuit current, and maximum power point voltage, which can cause MPPT to be unable to effectively track maximum power and affect system performance.

Improper parameter settings of MPPT itself: The working voltage range, current limit, maximum power tracking algorithm and other parameter settings of MPPT do not match the actual photovoltaic modules or loads, which can also cause faults.

Solution:

Check the wiring connections: Carefully check if all wiring connections are correct, ensure that the positive and negative poles are connected correctly, and there are no cross connections or short circuits.

Tighten connection parts: Tighten all line connectors, plugs, etc. to ensure a secure connection. At the same time, check for oxidation, corrosion, and other conditions at the connection points, and if necessary, clean or replace them.

Matching photovoltaic modules: When selecting photovoltaic modules, try to choose modules with consistent or similar parameters for parallel connection. If there are already parameter differences, grouping, series parallel combination, and other methods can be used to make the parameters of the components connected to each MPPT relatively balanced.

Optimize MPPT parameters: Based on the actual parameters of photovoltaic modules and loads, set the operating voltage range, current limit, and other parameters of MPPT reasonably. At the same time, according to the lighting conditions and system operation, adjust the relevant parameters of the maximum power tracking algorithm to improve the tracking efficiency of MPPT.

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