Abstract: A lock system, comprising at least one off-line lock and at least one key, e.g. as a key card with encoded data, said lock including an electro/mechanical locking mechanism which can be affected by the key, and a key reader enabled to read the encoded data on the key, memorize said data and compare these data with data stored in the key reader for the purpose of, depending of certain comparable data, affecting the locking mechanism. The data used in the system comprise user identification, lock identification, valid time window and also override criteria e.g. time related criteria for invalidating prior used keys.

Abstract: Recodable electronic lock where the coding unit which contains the code and/or other readable information preferably is removed from the lock after the recoding operation. The lock is coded by help of input of information and brought to accept recoding to any code member in a series of code members and is valid until a new, previously not utilized code member in this series is introduced whereupon the lock is automatically recoded to this new code so that the previously employed code member(s) are no longer accepted. The lock is then recoded to accept a new code series by employment of a new appropriately coded recoding member which contains readable information about the code(s) of the different code members in the new series. The potentially valid code series are stored in a memory unit in the lock.

Abstract: A lock system, comprising at least one off-line lock and at least one key, e.g. as a key card with encoded data, said lock including an electro/mechanical locking mechanism which can be affected by the key, and a key reader enabled to read the encoded data on the key, memorize said data and compare these data with data stored in the key reader for the purpose of, depending of certain comparable data, affecting the locking mechanism. The data used in the system comprise user identification, lock identification, valid time window and also override criteria e.g. time related criteria for invalidating prior used keys.