Extra-low voltage or ELV – in Electrical or technical definition of an Extra Low Voltage system refers to the system which operates in voltage not exceeding 50 V AC (or 60 V DC),  but in the construction industry an ELV system refers to the system which needs electricity to work but it is not the part of the building’s main electrical system and not exceeding 50 V AC or 120 V DC.
In a nutshell ELV, some people referring ELV as Building Technologies because its involved many systems and different technologies or protocol, mostly silo or not connected.
The last 10 years, advancement in digital technologies have transformed the ELV equipment into IP based and addressable devices. Most of these systems are programmable and be part of bigger network.
ELV has a wide Scope of Works (SOW) and system components, there are:
- Physical Security
- Fire & Evacuation
- Structure Cabling & Comm
- FTTH and Fiber Optics
- Industrial Appliances & Racking
- IP Audio & Video
- Car Park System & Traffic Control
- UPS & PSU & PDU
- ICT Networking Switches
- Control Room & Data Center
- Wireless Indoor & Outdoor
- Wiring Tray, Trucking, Ladder & Ducting
- Telecommunication
ELV is closely tight together with construction, it is because during building construction period, all building systems should be pre plans, designs and approve before construction commerce. Thus, when the building is hand over, all systems are in operation, conceal and in protect condition.
It is more costly, to setup and commission ELV system after the building is handover because wiring provision, Interior design finishing, facade and etc.
