Intercom System operation

Video door PHONE (also known as a video intercom or doorphone) is a stand-alone system used to manage calls made at the entrance to a building (residential complex, detached family home, workplace, etc.) with access controlled by audiovisual communication between the inside and outside. The main feature of video door entry is that it enables the person indoors to identify the visitor and, if (and only if) they wish, engage in conversation and/or open the door to allow access to the person calling.

When a visitor arrives at the entrance to the condominium, screening by the security guard is carried out. The guard will call the resident via the guard unit for verification. The Audio/ Video Intercom unit of the apartment concerned will chime to alert the resident. The resident answers the call by lifting the handset and talk to the guard. The call shall be cut off automatically upon replacing the handset.
The visitor proceeds to the respective private/ passenger lift lobby entrance and presses the call button of the apartment, from the visitor call panel. The apartment Audio/ Video Intercom unit shall chime (a different tone to differentiate the call from the guard porter station) and the video image of the visitor shall be transmitted to the apartment video monitor. The resident may answer the call by lifting the handset and communicate with the visitor.
The resident can grant access to the visitor to get into the Private/ Passenger lift by pressing the dedicated release button on the Audio/ Video Intercom unit. Simultaneously, a voltage free contact will be sent to the lift control system (by others). The lift supervisory panel shall respond to this signal by homing the lift to the ground storey or Basement Level and enable the visitor to enter lift and board the lift to the designated floor of the resident only.
There shall be two-way communication between the visitor call panel and the Apartment intercom set, the visitor call panel and the guard unit at the Guardhouse, the guard unit at the guardhouse and the apartment set, the guard unit at the Guardhouse and the Management Office set, the apartment set and the Management Office set.
Each lobby call panel should have its own speech path within its own tower block.
Calling of the apartment intercom unit from the visitor call panels or guard unit shall be via a programmable 4-digit code number.
The system shall be able to operate normally, even if one or more of the apartment video intercom unit is left "off-the-hook".
The system shall be interfaced with the Security Card Access Control System to control the opening/ closing the main door and of the Private/Passenger Lift doors by the residents.
Notwithstanding the above performance Specifications, the tenderer is to submit detail operation facilities and functions c/w relevant technical catalogues for Audio/ Video Intercom System including guard unit, visitor call panel, apartment unit set, etc.