If a current of 30mA is already dangerous to humans, depending on the time, then what is a 300mA IDR for? Can I use it in my facilities? In this video, we will answer all these questions in theory and in practice. Get ready for a great lesson on protection against electric shocks. So tune in! ANDRA Online Store: https://bit.ly/loja-andra ANDRA Website: https://bit.ly/site-andra STECK Website: https://bit.ly/site-steck _________________________________________________ Receive Eletricity content directly in your email! Register using the link below: ???? https://bit.ly/cadastro-eletricity __________________________________________________ ???? Check out our content ???? ???? https://linktr.ee/Eletricity __________________________________________________ We've already said here on the channel that an IDR cannot operate up to 50% of its nominal value, it can operate from 50% up to the nominal value and must operate from 100% up to values ​​above in very short times. This rule also applies to a 300mA IDR that can only operate from 150mA. If we analyze this table, we can see that currents greater than 100mA can cause cardiac arrest. If we check the nominal value of the IDR, 300mA already goes through to severe burns, necrosis and instant death. In the video, we did a test where we installed a 30mA IDR to protect the circuit and used our human body resistance simulator. We have an indication of current circulation with the LED going out, but the circuit's IDR activated, preventing the shock for a very long time. With the 300mA IDR, only our simulation device activated, which indicates that there was a fatal electric shock. So what is a 300mA IDR for? There are two ways to protect someone from electric shocks. This can be done before someone suffers a shock or exactly at the moment they suffer. I'll explain. But first, let's recap what we've already shown several times here on the channel about item 5.1.2.2.4 Automatic power supply disconnection in NBR5410. In this item, the standard states that a protective device must automatically disconnect the power supply to the circuit or equipment it protects whenever a fault (between a live part and ground or between a live part and a protective conductor) in the circuit or equipment gives rise to a contact voltage higher than the UL limit contact voltage value. Let's also remember what we've already said about TT and TN grounding. I left some video cards on the screen. Basically, in the TN scheme, we have neutral and ground connected to the BEP, and in the TT scheme, this connection does not exist. Let's now imagine that a phase has come into contact with a grounded housing. If the scheme is TN, the fault current will be very high, since it is also a short circuit due to the connection between neutral and ground. So I can use a circuit breaker to turn off the circuit before anyone gets an electric shock. Now let's imagine that the scheme is TT. Since there is no connection between neutral and ground, if the same phase touches the grounded housing, we now have a current flowing and its value is low, since it depends on the grounding resistance, so a circuit breaker cannot detect this fault and would not be able to act to protect against shocks. This is where the IDR comes in and yes, it does not necessarily have to be 30 mA. Do you know where you can find the entire line of STECK IDRs with the best cost-benefit? At ANDRA, the largest electrical materials chain in São Paulo. There are more than 10 stores spread throughout the Southeast, in addition to service throughout Brazil through telesales, WhatsApp or Virtual Store in partnership with Portal Elétrico. Visit “andra.com.br” and learn more. To see more videos with STECK products here on the channel, leave your suggestions in the comments. Take the opportunity to access the description of this video, links to more details about STECK, ANDRA and the products shown in this video. Until next time! ???? Check out #eletricity #andra and #steck ???? __________________________________________________ Production and Editing. ???? Adoniran Freitas ???? Afrânio Freitas ???? Maecilei Leal ???? Dálcio Araújo __________________________________________________ Support: Life Print Company. ???? http://printcompany.com.br/site/