---
title: Lighting Controls
tags:
  - topic/construction/electrical
  - type/encyclopedia
---
# Lighting Controls

## Sensor Types

* Occupancy
* Vacancy
* Daylight
* Partition

## Occupancy/Vacancy Sensor Technologies

* Passive Infrared (PIR)
* Ultrasonic
* "Dual Tech" (PIR and ultrasonic)

## Switching/Communication

Dimming Terms
* **trim** --- refers to the minimum and maximum brightness levels
    (low-end and high-end trim respectively)
    a dimmer will reach. Usually adjustable.

### Line Voltage

120--347VAC

### Low Voltage

24V Class 2 control circuit

### Digital

#### Generic "Standalone"

The examples below are typical of a generic system,
with functionally identical features and topologies.

Includes wired (via [[twisted-pair-cable]] and 8P8C "RJ-45" connectors)
and wireless (via RF) communication.

* [Legrand Wattstopper Digital Light Management (DLM)](https://www.legrand.us/solutions/digital-lighting-management)
* [Acuity nLight®](https://nlight.acuitybrands.com/overview)
* [Lutron Vive](https://commercial.lutron.com/us/en/commercial-systems/vive)
* [Cooper Greengate](https://www.cooperlighting.com/global/brands/greengate)

#### Digital Addressable Lighting Interface (DALI) ^dali

[Digital Addressable Lighting Interface](https://en.wikipedia.org/wiki/Digital_Addressable_Lighting_Interface)

Open protocol defined by [IEC 62386](https://www.dali-alliance.org/standards/IEC62386.html).

4-Conductor Class 2 control circuit

%%
Lutron's QS bares some resemblance to DALI.
%%

#### Digital Multiplex (DMX) ^dmx

[DMX512](https://en.wikipedia.org/wiki/DMX512)

DMX512-A defined in ANSI E1.11-2008

Shielded [[twisted-pair-cable]] with XLR or 8P8C "RJ-45" connectors

#### See Also

> [!quote] [BACnet](https://en.wikipedia.org/wiki/BACnet)
> **BACnet** is a communication protocol
> for building automation and control (BAC) networks.
> It is defined by **ANSI/ASHRAE 135** and **ISO 16484-5**.

[[twisted-pair-cable]]

## Dimming Technologies

* Triac (Line voltage dim)
* Analog (0-10V dim)
* Digital

All these control methods are likely to appear in drawings.

### 0-10V Dimming

[0-10 V lighting control](https://en.wikipedia.org/wiki/0-10_V_lighting_control)

In conduit:

```
Southwire 64350501
SIMpull® 16/2 Low Voltage Signal Cable, Blue
```

This method is compliant with
[[nfpa-70_725_control-circuits#725.136(I) Other Applications.|NEC 725.136(I)(1)]],
which allows control circuits to share a raceway with power conductors
if either all of the power conductors or all of the control conductors
are themselves in a raceway,
or in metal-sheathed, metal-clad, non--metallic-sheathed, or Type UF cable.

### Triac Dimming

Triac dimmers work by chopping the AC power waveform.
This reduces the output power, so the lamp dims.

> [!info]
> "Triac" refers to the electronic component
> that does the wave-chopping.

#### Subtypes

There are two subtypes based on which side of the wave is chopped.

* **Magnetic Low Voltage (MLV)** -- AKA "Leading Edge" or "Forward Phase"
* **Electronic Low Voltage (ELV)** -- AKA "Trailing Edge" or "Reverse Phase"

The "magnetic" and "electronic" of MLV and ELV
are holdovers from pre-LED days,
having nothing to do with how they are used today.
They are, unfortunately, the most common terms.

> [!important]
> "Triac" is sometimes used in contrast to ELV erroneously to mean MLV

There also exist "universal" or "phase select" dimmers,
which can be switched between the two subtypes.

### Digital Dimming

> [!info]
> It is likely that "digitally dimmed" fixtures are 0-10V dimmed internally.
