20.500.12556/RUL-172587 Zaščitne naprave na diferenčni tok Protective Devices for Residual Current Diplomska naloga obravnava testiranje zaščitnih naprav na diferenčni tok (RCD) kot ključen element varnosti v nizkonapetostnih električnih inštalacijah, s poudarkom na njihovem delovanju, pravilni uporabi, tipičnih napakah v inštalacijah ter vplivu uhajavih tokov in DC komponent na njihovo zanesljivost. V teoretičnem delu so predstavljeni tipi RCD stikal (AC, A, B, B+), njihova uporaba glede na namen zaščite ter vezave v različnih električnih sistemih (TN, TT, IT). V osrednjem delu naloge so analizirane najpogostejše napake v povezovanju EFI-stikal, med katerimi izstopa neželena ponovna združitev nevtralnega (N) in zaščitnega (PE) vodnika. S pomočjo računske analize je pojasnjen vpliv te napake na tokovno porazdelitev in sproženje zaščitne naprave. V eksperimentalnem delu so izmerjeni uhajavi tokovi različnih gospodinjskih naprav. Rezultati so potrdili, da se uhajavi tokovi različnih naprav seštevajo in povzročijo neželeno proženje zaščitnih naprav, če je na eno stikalo priključeno preveliko število naprav. Na podlagi meritev so bila oblikovana priporočila za načrtovanje tokokrogov z EFI zaščito, ki vključujejo omejevanje števila naprav na posamezno stikalo glede na njihove karakteristike. Eksperimenti so bili izvedeni v podjetju ETI, specializiranem za proizvodnjo zaščitnih stikal in sorodnih elektrotehničnih naprav. Poleg tega so bile izvedene meritve vpliva DC-komponente na delovanje EFI stikal tipa A. Analiza je pokazala, da prisotnost enosmernega toka povzroči nasičenje magnetnega jedra v RCD in lahko zmanjša njegovo zanesljivost delovanja. Tip A se je izkazal kot neustrezen pri prisotnosti trajnih DC komponent, zato se v takih primerih priporoča uporaba naprav tipa B ali B+. This thesis examines residual current devices (RCDs) as a key element of safety in low-voltage electrical installations, with a focus on their operating principles, correct application, typical installation errors, and the influence of leakage currents and DC components on their reliability. The theoretical part introduces the different types of RCDs (AC, A, B, B+), their applications depending on the intended protection, and their implementation in various earthing systems (TN, TT, IT). The core of the thesis addresses the most frequent wiring faults involving RCDs, with particular attention to the unintended reconnection of the neutral (N) and protective earth (PE) conductors. Numerical analysis is used to explain the impact of this fault on current distribution and RCD tripping behavior. In the experimental part, leakage currents of several household appliances were measured. The results confirmed that leakage currents from multiple devices add up and can cause nuisance tripping of RCDs if too many appliances are connected to a single device. Based on the measurements, guidelines for the design of RCD-protected circuits were developed, including limiting the number of appliances connected to one RCD according to their leakage characteristics. The experiments were conducted at ETI, a company specializing in the production of protective devices and related electrotechnical equipment. In addition, tests were carried out to investigate the effect of DC components on the performance of type A RCDs. The analysis showed that the presence of direct current causes saturation of the RCD’s magnetic core and reduces its operational reliability. Type A devices proved unsuitable in the presence of permanent DC components; therefore, the use of type B or B+ RCDs is recommended in such cases. zaščitna stikala diferenčni tok EFI uhajavi tok RCD električne inštalacije DC analiza residual current devices RCD EFI leakage current differential current electrical installations DC analysis true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-09-09 11:55:21 2025-09-09 11:55:28 2025-10-16 03:50:19 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1970-01-01 62910 Barlic_Lara_-_Zascitne_naprave_na_diferencni_tok.pdf Barlic_Lara_-_Zascitne_naprave_na_diferencni_tok.pdf 1 400161D1F2B771EA0FC5F9A7B59726B9 d884b2caaf7691a24846a392a2f758998194c91912acdda087924df338f29a0b f588e6d8-8d62-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=216493 Fakulteta za elektrotehniko 0 0 0