No need. Just install that mismatch module which has hot spot, shaded, degradation fast, dusty etc.
Suggested install all the modules under one MPPT. If just install the mismatch module can only solve the mismatch in the string, not solve the mismatch issue among the strings. Only fully installed can solve mismatch issues in single string and among the strings, thus will get the best performance to save as much as power losses.
It will solve the mismatch issue in certain period. The mismatch status is not constant, it will change with the different module degradation level while time lapsing, environment changing etc. The mismatch issue may happen again at other module after a certain time. Referring to the barrel effect, the system will appear heavy power loss. Need to find out the mismatch module to deal with.
After the project running few years, the project with shadow, dust, bird shit, hot spot, different degradation among modules, voltage mismatch among the strings. The ROI will be high if the project with high FIT.
Due to the basket effect, if there is one module has issue thus it’s current will go down, and thus the whole string current will be dragged down and result in the normal module will loss the power generation. Optimizer can work on the abnormal module through by rising current & low voltage to save the power from the normal module.
Optimizer can use all the module under 72x166mm cell, 182 1/2cell, 210mm 1/3 cell. The latest 182 and 210cell module (above 15A) are not supported yet, current higher than 15A are not suggested. If customer insist to install need to provide PV module, inverter, location, system diagram information to evaluate in advance. 500w+ PV module is designed for solar farm, but some Residential and commercial customers project will install it need to evaluate in advance.
Current competitor optimizers are made by electrical components. Normally has around 150 components in one optimizer. Peak efficiency is 98% above. Big and not cheap. Ours is made by chip, the components are only a few, the peak convention efficiency is 99.5%. Smaller, cheap, flexible, monitoring platform has extensibility.
As there is a fire on the PV rooftop, the fire fighters can not put out the fire due to there is high voltage on the PV module, they only can work after the the fire terminate by itself. So RSD is a compulsive requirement for US PV project and some EU countries is looking into RSD.
RSD default status is shutdown status, limit each module under 1V。RSD connect to a gateway in each string, all the gateway connect to one controller. There is a physical switch on the controller to turn down the whole string voltage. If the string is burned, the RSD also is in the shutdown module mode as the RSD can not get the signal (the system is working normal signal) from the gateway.
NEC 2017 690.12, when there is a fire, the voltage must under 80V between 1ft(0.31m) array boundary within 30S.
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