Specifications

Level One: Protege GX Installer Study Guide | August 2013 91
Elevator Control
Interfacing with elevator controllers to achieve access control to floors can be done either high level or low level.
Configuration of elevator control is not covered in this module which simply aims to advise what equipment is
required to achieve low level elevator floor control.
Low level elevator control is achieved by controlling the user's ability to select floors in the elevator car. This is
done by supplying a set of clean contacts to the elevator control system for every floor that needs to be locked
off. The access control system then enables and disables floors by changing the state of the contacts.
Typically, when a user badges their card at the reader located in the elevator car, the access control system
turns the relays on for the floors that the user is allowed access to. After the lock timeout, the relays are turned
off again, locking the floor select buttons off again.
There are two main problems with this:
1. Security: For the period that the relays are on, multiple floors can be selected. Two people could enter an
elevator, one could badge their card and select a floor. The other could then press buttons until another
floor is selected.
2. Reporting: There is no way for the security system to report on where the user went, or if indeed access
was taken. All we get is an access request.
Destination Reporting
Destination Reporting can be implemented to improve security. This involves providing a set of isolated inputs to
the elevator control system, which receive feedback on which floor buttons are pressed.
With Destination Reporting enabled, the user badges their card, the floor relays energize for the floors they are
permitted access to, but now when they select a floor the system sees the button press. In response, the
system turns the floor relays off to prevent any other buttons being pressed and logs an event showing which
floor the user selected.
Hardware Requirements
At this stage, there is not yet a full DIN Rail solution so implementing elevator control in Protege GX requires
PCB hardware.
 An intelligent reader expander (RDI2 or RDE2) is required for every two lifts you need to control. Each
expander provides two reader ports, one per lift car.
 The secondary RS-485 port is used to interface with PX16 output modules which become dedicated for
low level elevator control.
 PX16 expanders are added based on number of floors that require controlling. The last PX16 added can be
split in half if required with the first 8 relays controlling one lift car and the second 8 relays controlling the
second lift car.
 For Destination Reporting, Protege Destination Reporting Interfaces (PRT-PX16-DRI) are interconnected to
the PX16 modules.