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Link to purchase the Electrical Calculations Spreadsheet: https://hotm.art/ytd-planilha-calculo... Link to purchase the Load Panel Calculation Spreadsheet: https://hotm.art/ytd-planilha-quadro-... Link to purchase the Electrical Plant Sizing Spreadsheet: https://hotm.art/ytd-planilha-plantas... __________________________________________________ If you like the Eletricity channel and want to contribute to the generation of quality content, then access one of the options below: PIX KEY ???? [email protected] QR CODE ???? https://bit.ly/doacao-pix __________________________________________________ ???? Check out our content ???? ???? https://linktr.ee/Eletricity __________________________________________________ Basically, the TN-C grounding scheme is one in which the protection and neutral functions are performed by a single conductor. In other words, the neutral conductor accumulates both functions and is now called PEN (PE protective conductor + neutral conductor). To assemble the TN-C grounding scheme, I have to ground my power supply, that is, connect the neutral to my grounding system. But pay attention, this is not the functional grounding of the utility company where the neutral is normally grounded. I am talking about my grounding system composed of grounding electrodes built exclusively for equipotentialization and grounding of metal masses and structures. Now let's look at the restrictions of the TN-C scheme according to NBR-5410: 5.1.2.2.4.2 – F) In the TN-C variant of the TN scheme, the automatic sectioning function for protection against electric shocks is not allowed to be assigned to DR devices. NOTES – 1) To make the use of the DR device possible, the TN-C scheme must be converted, immediately upstream of the device installation point, to a TN-CS scheme. That is: The PEN conductor must be separated into two distinct conductors for the neutral and PE functions, this separation being made on the source side of the RCD device, with the neutral conductor then passing internally and the PE conductor externally to the device. 5.4.3.6 – In every building supplied by a power line in a TN-C scheme, the PEN conductor must be separated, from the point of entry of the line into the building, or from the main distribution panel, into distinct conductors for the neutral and protective conductor functions. The power supply, until then TN-C, then becomes a TN-S scheme (globally, the TN-CS scheme). Observing the texts of the standard above, we can conclude that the separation of the neutral into two conductors from the distribution panel is mandatory and by carrying out this procedure it is possible to use the RCD even if there is a TN-C grounding scheme at the input, which is converted to TN-S from the distribution panel and becomes a scheme globally known as TN-CS. What needs to be very clear is that once the PEN conductor is divided into two conductors (protection and neutral) in the distribution panel, they can no longer be joined together. So making a jumper between the neutral and ground of an outlet is a hack, just like making a jumper between the neutral and ground of a shower. Here on the channel, you must have heard the terms “grounding scheme”, “equipotentialization”, “grounding electrodes” and “BEP” a lot. Let’s break down the terms a little more so you can understand them better: Grounding scheme – Format or characteristic of your grounding assembly according to the 4 conditions allowed by the standard (TN-C, TT, IT, TN-S). Equipotentialization – Placing all the masses (metallic) and metallic structures of a building at the same electrical potential. Grounding electrodes – Set of cables, rods, connectors and other accessories that make up a grounding system. BEP – Main equipotentialization busbar. There is another important restriction regarding the use of the TN-C grounding scheme. The PEN conductor cannot have a minimum cross-section of less than 10mm². This grounding scheme can also be very bad for your installation if there is a loss of neutral or overvoltage. It is not the most recommended, but if there is no possibility of installing another grounding scheme, it is a way to offer the minimum protection and safety for your installations. In other words, only use the TN-C scheme when there is no possibility of using another grounding scheme. If construction has not yet started, then give preference to the TN-S grounding system, which is considered by us at ELETRICITY to be the safest grounding scheme to be implemented. ???? Check out #eletricity ????