Why History of Methods of Key Control is Relevant
So, history matters because technology products are supposed to evolve….
When we originally started key control, our engineer designed our system to control the keytags using bar codes. When the drawer was opened, rows of optical scanners in the bottom of the drawer would compare which tags were withdrawn or replaced and compare it to the last information from the previous user of the drawer.
As time progressed we realized bar codes wore out, could become unreadable if scratched or dirty. Nothing prevented a user from returning those tags, but the next user wouldn’t be able to find the key, since it had been returned but not read, thus requiring a physical audit.
It is completely incomprehensible that companies are still out there selling systems that use bar code technology.
Now, many key management systems use what is known as a dallas touch memory, to control keytags. The primary reason is because it is cheap and technically easy to read the unique ID by 1 data wire and ground, which means that the cost of the reading mechanism is low. These devices are essentially touch memories.
Contact based, they require metal to metal electrical contact. This is best described like an audio jack plug. The keyTag contains memory which is electrically connected to the metal housing. The housing generally has a plastic ring separating the two electrical connections. When it is inserted in to the cabinet or drawer, metal spring contacts mate with the surface to provide power and read the identification number of the chip.
RFID is more reliable than contact identification or bar code scanning and is why deister key management systems use RFID keyTags to provide maximum operational life with minimum cost.