Porque as LÂMPADAS ENFRAQUECEM ao LIGAR o CHUVEIRO? 🤔😧

⚡️ MEGATRON WEBSITE: https://eletr.co/megatron_221023 ------ ⚡ FREE CLASS: How to Do a Complete Electrical Installation From Scratch, Easily, Even if You're Not a Professional Electrician: ➽ https://eletr.co/aula?utm_content=MsP... -------------------------- 📣 FAAALA ENGEHALL COMMUNITY 📣 Join our WhatsApp community to receive valuable tips and news in the electrical field, important information and much more. 😉 ➽ https://eletr.co/fala-eng -------------------------- Did you like this video? 😍 ✔️ Leave your comment and share with your friends ✔️ Follow our networks ➽ https://eletr.co/links?utm_content=Ms... -------------------------- 👉 NR10 Course with 20% discount ➽ https://eletr.co/nr10?utm_content=MsP... -------------------------- Why do LIGHT BULBS DIMINISH when you TURN ON the SHOWER? 🤔😧 My dear, have you noticed that in some homes, when you turn on the shower, the lights get dimmer, and in some cases, even some appliances stop working? Well, in today's video I'm going to teach you three things: 1 - What is this voltage drop? 2 - How to find out which cable is suitable considering this drop? 3 - Two ways to solve the problem of light bulbs dimming when you turn on the shower? Well, let me tell you right away that there's nothing mysterious about it; what's happening is simply one of the consequences of voltage drop. Voltage drop is an effect caused both by an increase in the distance traveled by the electric current in a circuit, and also by the circuit being improperly dimensioned. Therefore, knowing how to correctly dimension an installation makes all the difference. And although many electricians ignore this problem, we're going to teach you how to do the correct calculations so you know how to solve this problem, because sometimes simply increasing the cable section by one section won't solve the problem. Item 6.2.7 of NBR 5410 presents the maximum permitted values ​​for voltage drop in detail. In summary, NBR 5410 defines that the maximum voltage drop in terminal circuits of use should not exceed 4% of the nominal voltage, and the total voltage drop along the circuit should not exceed 6%. So, how do you know which cable to use to avoid voltage drop? That's simple, my friend, just use the following formula: Sc = I x (L x 2) 58 x ΔV Where: S = Cable cross-section (mm²) I = Circuit current (A) L = Circuit distance 58 = Copper conductivity ΔV = Voltage drop value according to the circuit voltage Note that this formula is used for single-phase systems (127V / 220V) To understand better, let's look at a practical example, not so common but very didactic: I have a shower with a power of 5500W, installed 30 meters from my distribution board in a dedicated conduit. The voltage to power this shower is 127V. Therefore, applying Ohm's law, the current in this circuit is 5500W / 127V = 43.3A, without even considering the distance. Most "experienced installers" would use a 6mm² cable and a 40A circuit breaker because, according to them, it can handle it. But consulting table 36 of the standard, the 6mm² cable supports up to 41A in installation method B1. However, let's see what the correct cross-section is to meet the needs of this circuit. We already know that the circuit current is 43.3A. We also know that the circuit distance is 30 meters. The conductivity of copper, we also know, is a constant value of 58. Now we just need to calculate the voltage drop. As I said before, the voltage drop should not exceed 4%. In this case, we have 127V x 4% = 5.08V Now just substitute everything into the formula: Sc = 43.3 x (30 x 2) = 2598 = 8.81 58 x 5.08 294.64 The cable cross-section to serve this circuit for maximum efficiency should be 10mm², since there is no "gauge" of 8.8 mm². Okay André, fine, the shower cable in this case is poorly sized, but why does this affect the entire installation, causing the lights to flicker or dim? Unfortunately, the electric shower is still the villain of the electricity bill! Its power is very high, and more and more showers are being released that heat up more, thus consuming more energy. Even if you correctly size the shower circuit, in this case using 10mm² cable, it's useless if the house's power supply is poorly sized! Here in Minas Gerais, there are still many single-phase 40A systems with 6mm² cable supplying an entire house. In rural areas, it's even more common for the electrical panel to be close to the distribution pole (because CEMIG limits it to 30 meters) and very, very far from the house itself. I myself have installed rural overhead lines of 100, 200 meters, and some of them, unfortunately, without being able to change the panel due to customer issues. When you turn on the shower in this type of distant network, brother, the voltage drop is drastic, affecting the operation of the lights, appliances, and everything else connected!