---
tags:
  - type/encyclopedia
title: Low Voltage Systems
up: "[[electrical-construction]]"
---
# Low Voltage Systems

> [!info] See Also
> * [[emergency-communications-systems]]
> * [[fire-alarm]]

## Radio Repeater Systems

### Bi-Directional Amplifier (BDA)

Used to facilitate radio (usually cellular) communication
where it is inhibited by the facility structure.

Consists of a donor antenna, bi-directional amplifier,
and any number of remote units
where hard-wired connections to the BDA can be made.

### Distributed Antenna System (DAS)

Used to extend wireless communication throughout a facility.

While active DAS can be said to _require_ a BDA system,
in practice a "DAS System" almost always refers
to all the equipment required for its operation.

## Security Systems

### Electronic Security System (ESS)

### Intrusion Detection System (IDS)

### Access Control System (ACS)

### Video Surveillance

> [!info] Also Known As
> * Closed-Circuit Television (CCTV)

## Communications

### Telecommunications (Telecom)

> [!info] Also Known As
> * Voice/Data

### Structured Cabling:

Refers to a standardized architecture
of telecommunications cabling and equipment.

Architecture is star-shaped, paralleling building electrical distribution.

* Main Distribution Frame (MDF)
* Intermediate Distribution Frames (IDFs)

### Community Antenna Television (CATV)

Used to deliver radio frequency (RF) or digital television programming signals
from a single antenna to multiple devices.
A building CATV system may include the "picking antenna"
or instead include connection to a local utility's.

## Sound Systems

### Intercommunications (Intercom)

### Audio Visual (AV)
