Kodlås






Franskt kodlås


Ett kodlås är ett lås som öppnas med en sifferkod (eller annat lösenord). Denna typ av lås har fördelen att nyckeln inte fysiskt kan förkomma eller stjälas. En rent mekanisk implementation är de kombinationslås som i många decennier använts för kassaskåp.


Till vardags används beteckningen oftast om elektroniska lås i portingången till lägenhetshus och företag. På de enklaste varianten trycker man in en fyrsiffrig kombination som får ett dörrelä att låsa upp dörren. När man behöver större säkerhet för att inte obehöriga skall komma in, så används ofta kodlås i kombination med kortläsare eller RFID-läsare. Kortläsaren ger endast tillträde, för de som har ett kort eller en RFID-tag samt kan koden (som kan göras individuell för varje användare). Koden kan styra både dörrelä och larmpåslagning/avstängning, och det är inte ovanligt att det räcker med kort eller kod dagtid, medan det på kvällar och helger krävs bådadera.



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