INTEGRATION COEFFICIENT IC EDUCATION PROGRAM
In a previous educational publication, always under our Integration Coefficient IC business model, regarding Central or String Inverters, we said that one of the most common cons of this type of system was, first, that they are relatively expensive to maintain since the installation can only be monitored at the system level and not at the level of each solar module because the solar panels were connected in series, so there is additionally a great risk of high voltage right on the roof of the residence, commercial or industrial customer, due to the sum of the open circuit voltages "Voc" of the solar panels in series.
The NFPA published the 2017 edition of the NEC (National Electrical Code in the USA), and technically as of January 1st of that year, any state could adopt the new rules of the code. Thus, any solar energy contractor installing an on-grid system had to be aware of the changes in the code. Previously, rapid shutdown requirements, according to the predecessor NEC 2014, only limited a high DC voltage for the wiring to be outside a certain perimeter around the total solar system.
Now, for solar On-Grid Installations, NEC 2017 in USA, added details by limiting the existence of that high voltage right at the level of the photovoltaic module due to its proximity to the roof. While there are several ways to achieve this, only one is possible with today's commercially available technology and standards. The idea was to isolate or separate PV modules connected in series, using electronics at the level of each one of them. Inverter manufacturers have taken the lead in offering solutions to comply with NEC 2017. A central inverter must be combined with some module-level technology. This already has a name, being called “Optimizers”.
With them, the first thing that is achieved is to locate faults for each photovoltaic module, thus preventing the failure of one of them from causing a total failure of the system, but even without eliminating the disadvantage of a single point of failure at the central inverter level, a disadvantage that is solved, as explained in other publications, with the use of Microinverters instead of Central inverters. Secondly, it is achieved that the DC voltage "seen" by the roof is equal to that of a single module, from 30 to 60 volts depending on the power of the solar panel, eliminating the high voltage produced by the sum of them when connected in series to the DC input of the central inverter that is located at ground level, thus complying with NEC 2017.
In our organization, and according to our Value Offer, we assign a lot of resources for educational programs to make installers, project designers, and end users aware of the advantages of the solutions created with our marketing and manufacturing business model Integration Coefficient IC. Please dive into our website to find more useful information, and please become our spokespeople when Contacting us.
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