ELV is the terminology used in the construction world in an attempt to electrically define all the systems in a building that need electricity to run but are not part of the building’s main electrical system. ELV covers all the new modern technologies that are increasingly becoming must-have systems in every building such as data networks, CCTV, fire alarm systems, public address systems, audio/video solutions, access control, intrusion detection systems, home automation, and much more!
The fact that such a broad range of technologies are collectively named “ELV” shows probably how much we are lagging behind the new demands of the 21st century. Below I will very briefly explain some of the confusing abbreviations that constantly pop up when discussing ELV systems.
LAN and WLAN
LAN stands for Local Area Network – also known as SCS (Structured Cabling System). Simply put, it is the data cabling in the building to enable users to network their computer devices and possibly access to the internet.
In a small building, this can be simply CAT6 cabling from an MDF (Master Distribution Frame – i.e. equipment rack) while in larger infrastructures, you usually see multiple IDFs (Intermediate Distribution Frame) interconnected by fiber optic cables. (It is interesting to know that while we have no electricity passing fiber optic cables, they are still categorized as “ELV”!)
WLAN stands for Wireless LAN which is the network of wireless access points that provide wireless network coverage within and outside the building.
As the technologies enhance, more and more other ELV systems depend on LAN infrastructure of buildings.
Telephony Systems
An IP PBX is a private branch exchange (telephone switching system within an enterprise) that switches calls between VoIP (voice over Internet Protocol or IP) users on local lines while allowing all users to share a certain number of external phone lines.
Closed Circuit TV (CCTV)
CCTV stands for Closed Circuit TV (again a very old acronym that shows the old “electrical” roots of such systems). Simply put, these are the camera systems set up inside and outside of buildings to provide monitoring surveillance. Old analog cameras used separate cabling of coaxial cables connecting each camera directly to the DVR (Digital Video Recorder). These are also today almost totally replaced with IP Cameras utilizing the common LAN infrastructure of the building.
Access Control System (ACS)
ACS is the abbreviation for Access Control System. ACS systems give access to different building locations (usually implemented by automatic unlocking of doors) through different means of authentication of people (by magnetic or RFID identification cards, by fingerprint, IRIS, or face recognition). Almost all new ACS solutions also rely on LAN infrastructure to some extent, while they also include electrical cabling to magnetic door locks, manual push buttons, and magnetic sensors installed on the doors and entry gates.
Public Address System (PAS/PAGA)
PAS (Public Address System) or PAGA (Public Address and General Alarm) is the speaker system installed in buildings for making announcements, playing background music and broadcasting pre-recorded alarm notifications, sometimes automatically triggered by fire alarm systems. PAS is probably one of the few ELV systems that is still not much IP-based and use twisted-pair electrical cables for connecting the distributed speakers to the power amplifiers. However, most newer PAS systems have accessories to enable utilizing LAN infrastructure for interconnecting the main components and provide a distributed design.
SMATV / CATV / IPTV
SMATV (Satellite Master Antenna Television), CATV (Cable Television), and IPTV (IP Television) all explain different technologies to provide a TV distribution system within a building, interconnecting multiple television sets to a single source (usually called Head End) so each television can select the desired watching channel from a selection list.
While SMATV and CATV have their separate cabling network based on coaxial (or sometimes fiber) cabling, they are rapidly being replaced with IPTV solutions that rely on the same LAN infrastructure jointly used by other systems.
Home Automation
Home Automation Systems include a very broad range of technologies for monitoring and controlling almost everything in the building from lights to doors to home appliances and audio equipment and in short whatever works with electricity in the building. Most home automation solutions are now network-based and give the option of remotely controlling and monitoring the building over the internet. While in the past, most home automation were using some remote control device, with advances of technology the means of control is now moved to smartphone and tablet applications or voice recognition solutions.
