Electrician's Table (Megatron) - https://www.engehall.com.br/tabela.el... ⚡️ FREE CLASS: How to Do a Complete Electrical Installation from Scratch, Easily, Even if You Are Not a Professional Electrician: ➽ https://eletr.co/aula?utm_content=yt1... ------ 📣 FAAALA ENGEHALL COMMUNITY 📣 Join our community on WhatsApp to receive valuable tips and news in the electrical area, important information and much more. 😉 👉 https://eletr.co/fala-eng?utm_content= ------ Did you like this video? 😍 ✔️ Leave your comment and share with your friends ✔️ Follow our networks ➽ https://eletr.co/links - - - - - - - - - - - - - - - - - - - - - - - - - - - 👉 NR10 Course with 20% discount ➽ https://eletr.co/nr10?utm_content=yt1... ------ Hey my dears, how are you? Welcome to another video in our SUPER EASY series here at Engehall! Electrical sizing... In addition to being the terror of many "E-LE-TRE-CIS-TAS", it is one of the doubts of several subscribers here on the channel. So, in today's video, offered by our partner Megatron Fios e Cabos, we will teach the step by step so that anyone can learn how to do the electrical sizing of a residence in a SUPER EASY way, let's go to class? So, guys, here's the deal... those famous little pocket tables for sizing electrical cables are a great help, right? Stay tuned because at the end of the class I have a surprise for you. After all, today we're going to learn a little more in depth how to size a circuit to power an electric shower, once again step by step, of course! First, we need to know what the minimum cross-section is that NBR 5410 recommends for electrical cables. To do this, let's consult table 47 of the standard and see what it says: For lighting circuits, the minimum cross-section of cables is 1.5 mm2. For power circuits (or socket circuits), the minimum cross-section of cables is 2.5 mm2. "So it's easy, Andre. I use 1.5 mm2 cable for lighting and 2.5 mm2 for the rest, right?" Wrong, my friend. This is where a lot of people make mistakes... Just because the standard recommends a minimum cross-section for a circuit, it doesn't mean it's the ideal cross-section for that circuit. I'll give you an example: To know which cable to use, we first need to know the load of that circuit. Take a look: Step 1: Find out the current A shower with a power of 5500W connected to a single-phase 127V network will consume an average current of 43A. So I already have the circuit current and, thinking roughly, I think the 6mm² cable would support this shower, right? Calm down, take a look: Step 2: Define which cable to use The next step is to choose the insulation of the cable I'm going to use. Will it be a cable with common 750V insulation? Or will it be one with 1kV insulation? Generally, for indoor installations, we use cables with PVC insulation (750V). For outdoor or underground installations, for example, we use HEPR or XLPE cables (0.6/1kV) because this cable has double insulation. For our shower, let's assume that it is inside the property, that is, it is internal. 3rd Step: Choose the nominal cross-section of the cable Once the cable insulation has been defined, in this case 750V, we will go to table 36 of NBR 5410 and consult the cross-section of the cable that supports 43A, according to each installation method and number of loaded conductors. But here's a break, let's understand what an installation method is and what the number of loaded conductors is. The installation methods basically refer to where these cables will be installed. Whether they will be embedded or exposed and also within what type of structure these cables are located. Table 33 of the standard lists all these methods. In our case, these will be cables embedded in the masonry, the reference method chosen by us will be B1. The number of loaded conductors, on the other hand, means the number of cables with current circulation in that circuit. For example: If we have a 127V circuit with phase and neutral, we have 2 loaded conductors. If we have a 220V circuit with only two phases, we again have 2 loaded conductors. If we have a 220V circuit with two phases plus neutral, then we have 3 loaded conductors. The grounding cable does not have current circulation, so it does not count as a loaded conductor. Thinking again about our shower, we only have phase, neutral and ground, in this case we have only 2 loaded conductors. Now let's go to table 36, about PVC conductors. Note that the reference temperature in the environment is 30 degrees, see below that for installation method B1, with 2 loaded conductors, the maximum current that a 6.0 mm2 cable supports is 41 A, so it will not meet our needs. We then move on to the 10.0 mm2 cable. Note that it supports 57 A, so it will be the cable we will choose to meet our example.