Time-delay combination locks

Use

Time-delay combination locks are frequently incorporated into money safes as an armed robbery deterrent. In many instances, time-delay combination locks are also equipped with a duress code which may be entered to activate the time delay whilst sending a silent alarm to a monitoring centre.

Modern time delay combination locks can have many functions such as multiple different codes, pre-set time lock settings (open and close times), pre-set vacation times (e.g. Christmas Day), dual code facility, and a full audit trail providing a detailed record of the lock history showing who opened the lock, when and how long it was open.

They also use a non-volatile memory so that no information is lost if the batteries are depleted. This will allow the safe to be opened when the batteries are changed after the pre-set time if the correct code is entered. Some electronic combination locks with a time-delay feature require the code to be entered twice: once to start the timer, and a second to unlock and open the safe entered after the delay period has expired.