ESQUEMA DE ATERRAMENTO TN-C – TUDO QUE VOCÊ PRECISA SABER.

🎁 Products we recommend: 🔗 https://meli.la/2njVbpU __________________________________________________ Automate your electrical calculations with our spreadsheets: Link to purchase the Electrical Calculation Spreadsheet: https://hotm.art/ytd-planilha-calculo... Link to purchase the Load Schedule Calculation Spreadsheet: https://hotm.art/ytd-planilha-quadro-... Link to purchase the Electrical Plant Sizing Spreadsheet: https://hotm.art/ytd-planilha-plantas... __________________________________________________ 👇 Check out our content 👇 🔌 https://linktr.ee/Eletricity __________________________________________________ Basically, the TN-C grounding scheme is one where the protection and neutral functions are performed by a single wire. The neutral conductor performs both functions and is then called PEN (protective conductor PE + neutral conductor). To assemble the TN-C grounding system, I have to ground my power supply, that is, connect the neutral to my grounding system. But note that 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 equipotential bonding and grounding of metallic masses and structures. Now let's look at the restrictions of the TN-C system according to NBR-5410: 5.1.2.2.4.2 – F) In the TN-C variant of the TN system, the function of automatic disconnection for protection against electric shocks cannot be assigned to residual current devices (RCDs). NOTES – 1) To enable the use of the RCD (Residual Current Device), the TN-C system must be converted, immediately upstream of the device's installation point, to a TN-C-S system. That is: The PEN conductor must be split into two distinct conductors for the neutral and PE functions, this separation being made on the source side of the RCD, with the neutral conductor then running internally and the PE conductor externally to the device. 5.4.3.6 – In any building supplied by an electrical line in a TN-C system, the PEN conductor must be separated, from the point where the line enters the building, or from the main distribution panel, into distinct conductors for the neutral and protective conductor functions. The electrical supply, up to that point TN-C, then becomes a TN-S system (globally, the TN-C-S system). Observing the text of the standard above, we can conclude that separating the neutral into two conductors from the distribution panel is mandatory, and by doing this, it is possible to use the RCD even if there is a TN-C grounding scheme at the entrance, which is converted to TN-S from the distribution panel and becomes a scheme globally known as TN-C-S. What needs to be very clear is that after the PEN conductor is divided into two conductors (protection and neutral) in the distribution panel, they can no longer be joined. Therefore, making a jumper between the neutral and ground of an outlet is a makeshift solution, as is making a jumper between the neutral and ground of the shower. Here on the channel, you have probably heard many terms such as "grounding scheme," "equipotential bonding," "grounding electrodes," and "BEP." Let's break down the terms a bit more so you can understand better: Grounding scheme – The format or characteristic of your grounding system according to the 4 conditions permitted by the standard (TN-C, TT, IT, TN-S). Equipotential bonding – Placing all (metallic) masses and metallic structures of a building at the same electrical potential. Grounding electrodes – The set of cables, rods, connectors, and other accessories that make up a grounding system. BEP – Main equipotential bonding bar. 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 neutral loss or overvoltage occurs. It is not the most recommended, but if there are no conditions to install another grounding scheme, it is a way to offer a minimum of protection and safety for your installations. In other words, only use the TN-C system when there is no possibility of using another grounding system. If construction has not yet begun, then give preference to the TN-S grounding system, which we at ELETRICITY consider the safest grounding system to implement. 💡 Stay tuned to #eletricity 💡