Okwamanje kweI-LEDukwanda ngenxa yezizathu ezahlukahlukene ezisetshenziswayo. Ngalesi sikhathi, izinyathelo zokuzivikela zidinga ukuthathwa ukuze kuqinisekiswe ukuthi i-LED ngeke yonakaliswe ngoba ukwanda kwamanje kudlula isikhathi esithile kanye nobukhulu. Ukusebenzisa amadivaysi okuvikela amasekethe kuyisilinganiso sokuvikela esiyisisekelo nesi ukongayo. Isici sokuvikela esisetshenziswa kakhuluIsibani se-LEDukuvikelwa kwesifunda kuyi-varistor.

I-Varistor isetshenziselwa ukuvikela izibani ze-LED. Kungashiwo ukuthi kungakhathaliseki ukuthi yikuphi ukunikezwa kwamandla, ukushintshwa kwamandla kagesi kanye nogesi womugqa osetshenziselwa izibani ze-LED, ukuvikelwa okunjalo kuyadingeka. Isetshenziselwa ukuvikela i-voltage ekhuphukayo evame ukwenzeka kunethiwekhi yamandla kamasipala. I-voltage ebizwa ngokuthi i-surge ikakhulukazi i-pulse high-voltage yesikhathi esifushane ebangelwa ukushaywa kombani noma ukuqala nokuma kwemishini kagesi enamandla amakhulu. Ukushaywa kombani kuyisizathu esiyinhloko. Isiteleka sombani singahlukaniswa sibe yisiteleka sombani oqondile kanye nesiteleka sombani ongaqondile. Ukushaywa kombani okuqondile kusho ukuthi umbani ushaya ngokuqondile inethiwekhi yokuphakela amandla, okuyinto eyivelakancane, futhi iningi lamasistimu amakhulu okuphakelwa kukagesi anezinyathelo zokuvikela umbani ngokwazo. Ukushaywa kombani okungaqondile kubhekisela ekuqubukeni okudluliselwa kugridi yamandla okubangelwa umbani. Lokhu kuhlasela kungenzeka kakhulu, ngoba ukuduma kwezulu okungu-1800 nemibani engama-600 kwenzeka emhlabeni wonke njalo umzuzu. Ukushaywa kombani ngakunye kuzobangela ukukhuphuka kwamandla kagesi kugridi yamandla eseduze. Ububanzi bokushaya kwenhliziyo ngokuvamile bumbalwa kuphela obucashile noma obufushane, futhi i-amplitude ye-pulse ingase ibe phezulu njengezinkulungwane ezimbalwa zamavolthi. Ikakhulukazi ngenxa ye-amplitude yayo ephezulu, inomthelela omkhulu ekulimaleni kwemishini kagesi. Ngaphandle kokuvikelwa, zonke izinhlobo zezinto zikagesi zingonakaliswa kalula. Ngenhlanhla, ukuvikelwa kokuhlinzwa kulula kakhulu. Vele wengeze i-anti surge varistor, evame ukuxhunywa ngokufana ngaphambi kokulungisa kabusha.

Isimiso sale varistor simi kanje: kukhona resistor nonlinear ukumelana yayo iseduze nesifunda evulekile ngaphakathi komkhawulo obekiwe ububanzi, futhi lapho voltage esetshenziswa idlula umbundu, ukumelana yayo iseduze zero ngokushesha. Lokhu kwenza kube lula ukumunca ukuhlinzwa. Ngaphezu kwalokho, i-varistor iyithuluzi elitholakalayo. Ngemuva kokumuncwa kokuhlinzwa, kungadlala indima yokuvikela.