Why control elevators?
Worldwide in most countries elevators are not equipped with access control. Instead the lift foyer on each floor is controlled by door access control, and often there is a concierge or security guard on site 24 hours a day.
However there are many benefits to installing elevator access control. It is possible to reduce costs in that each foyer does not need to be access controlled. With a suitable system users can be restricted to particular doors at particular times. Call destination reporting can be used to tell who went to which floor when. Intercom interfaces can allow the floor release to be triggered for visitor access.

Any of the readers supported by CS Technologies door access controllers are available for elevator access control also.

Elevator interfacing
There are several different methods of interfacing to elevators

• Low-level outputs only. With this method, relay expansion boards are fitted to a controller. Each elevator has an associated controller and expansion boards. The relay outputs are 'in series' with the floor call buttons within each lift. Unless the relay is turned on, the floor cannot be selected. When a credential is used in the elevator, a set of relays corresponding to the floors valid for that person at that time turn on, allowing a floor to be selected. Using this method means that no record of where each person went is maintained; the system only records that they were in the elevator. Also, it is possible to select multiple floors if the credential is programmed for more than one floor.
• Low-level outputs with inputs for call destination reporting. With this method an interface to the lift call buttons is made so that the system can detect which floor was selected. This interface is via an input expansion board. Depending on the elevator control system the inputs can be configured as either pre-sensing or post-sensing.
  • With pre-sensing the person's credential is read and the buttons for their valid floors are scanned, but no relays operate. When a valid floor is selected the appropriate relay turns on to allow the floor to be latched. This method ensures that only one selection can be made per credential presentation. This provides the highest security; however it relies on particular circuitry being available in the lift system whereby the state of the floor call buttons can be sensed by the system.
  • With post-sensing the person's credential is read and the appropriate relays are activated; when a floor selection is made that relay is left activated and the other relays deactivate. There is a chance that multiple floor selections will be latched with this type of system. With some elevators this is the only option available because of the elevator circuitry.
• High level interface - some elevators interface to security via a high level data link rather than the 'low-level' relays and digital inputs. With a high level interface call destination reporting is possible depending on the elevator control system. Currently we support Kone Type 1, Kone Type 2 and Otis high level interfaces. High level interfaces have the problem that all elevators are controlled through a single interface making a single failure take out all of the elevators. They also rely on reliable data communication for call destination reporting and if the communication speed is low this is not always possible. Because of the communications speed it is also possible to latch multiple floors with one credential presentation.

We also provide intercom interfacing to allow floors to be released remotely. The intercom can be triggered for a different release time to that when a credential is presented in the elevator.

Some things to look out for:

• Ensure that the system controls each elevator separately. In years gone by many systems were installed with a common output controlling each floor, meaning that when a credential is presented in one elevator the same button can be pressed by someone in another elevator.
• Ensure that the system allows timezone control separately for each floor, so that some floors can be permanently on security and others open for public access.
• Ensure that the system provides the ability to grant users access to different floors at different times e.g. level 1 24 hours a day and level 2 9-5 only.
• Ensure that the system allows only one floor to be selected per credential presentation, to stop multiple buttons to be chosen by possibly incorrect people.

Transactions
Everything that occurs with the controller is recorded. This includes the use of credentials, the use of intercom release buttons, and if appropriate hardware is installed the destination each user went to.

Settings
The following times are all programmable:

• Release time: The length of time each floor is released after a valid credential
• Public access time zone: When the floor will automatically lock and unlock
• Intercom release time: Where the system is equipped with appropriate hardware it is possible to release the floor for say a minute when a visitor needs to get in, and for only 5 seconds on a valid credential read.