Unlimited Possibilities of Connection——PoE LED Lighting

PoE Market Prospects

According to the survey data of Power over Ethernet (PoE) market and the forecast of global PoE market, the compound annual growth rate (CAGR) of the global PoE market is expected to increase by 13% (as shown in Figure 1) by the end of 2022, reaching US$1 billion.

Figure 1 Global PoE Market Forecast

(Data source: Research And Markets)

The most popular PoE products include switches, power supplies, IP cameras, VoIP phones, and wireless APs. According to the forecast of market research company Research And Markets, wireless APs and PoE Lighting will become the two main growth drivers of the PoE market in the next decade.

By 2025, wireless AP and PoE Lighting will gain 40% of the market share and dominate the PoE market. This development trend is mainly due to the sharp increase in demand for PoE applications in the energy, oil and gas, telecommunications, automotive and transportation industries.

PoE Advantages

According to David Rao, an engineer at Excelpoint, a technical authorized agent, POE has the following advantages:

Save time and money: Because no power cables are required, costs and installation time are reduced. Installation is also simplified because no mains wiring regulations apply and no qualified electrician is required.

Flexibility: Proximity to power is no longer a consideration, and devices can be placed anywhere a LAN cable can be run.

Reliability: Centralized power replaces low-cost wall adapters, allowing a single uninterruptible power supply to back up the system.

Security: Provides a stronger security protocol than wireless, enhancing protection against hackers.

Easy and convenient: It can transmit power and data at the same time, reducing wiring harnesses, efficient and convenient.

PoE LED Lighting Product Introduction

Project Background

The promotion of PoE LED Lighting is based on the newly launched IEEE 802.3bt standard, which also makes important improvements to traditional LED Lighting. The main driving force behind this improvement is the use of four pairs of network cables to transmit up to 90W of power over a cable up to 100m long. This allows multiple lamps to be connected using daisy chains, simplifying the installation process.

Application Scenario

POE can be applied to commercial buildings, stadiums, large infrastructure, smart homes. Combining PoE with lighting has exciting new advantages. For example, PoE can be used to power UVC lamps to attack viruses, including COVID-19.

Product Framework

A PoE Lighting system can be established by connecting a PoE switch or a non-PoE switch (with a PSE power supply) to PoE LED lamps and other accessories, such as wireless APs and IoT sensors. Users only need to use some mobile terminals or server clouds equipped with supporting software to control the entire LED lighting system.

A PoE lighting system consists of five basic components: a gateway, a user interface, a PoE switch (not a PoE switch + PSE power supply), PoE node lamps, and auxiliary devices such as sensors or switches.

The data and power reception of the LED lamp is achieved by adding a "node" inside the LED lamp housing and connecting it to the LED power supply and dimming input.

Figure 2 PoE Lighting system architecture and product framework

Implementation of PoE LED Lighting

Powering devices via Ethernet cables (such as Cat5e/Cat6/Cat6a, etc.) mainly requires two components: the power supply equipment (PSE) and the powered device (PD). The PSE is responsible for supplying power like a power source, while the PD receives and uses power (load). At the same time, in a PoE configuration, each LED lamp can be a standard RJ45 connector (plug and play device), so industrial Ethernet is also an indispensable and important component.

Figure 3 Ethernet Power Supply Block Diagram

PoE LED Lighting Switch--Power Supply Equipment (PSE)

According to different application scenarios, the PSE at the power supply equipment end can have three product types:

Figure 4 Three types of products at the PSE end

1. Endpoint PSE—PoE switch is the most convenient way to achieve PoE power supply. PoE switch directly connects to the terminal PoE powered device PD for power supply and data transmission;

2. Midspan PSE - also known as PoE injector, is generally used when there is no PoE switch in the network. Its main function is to transmit its own power and data signals from ordinary switches to the PoE powered device PD through the network cable;

3. Extender PSE—PoE extender, extends the transmission distance of PoE powered equipment to >100m.

ADI defines a proprietary standard, LTPoE++™, which defines specifications for powered devices (PDs) up to 90 W and supports multiple power levels: IEEE PoE (13 W), IEEE PoE+ (25.5 W), IEEE PoE++ (71 W), and ADI LTPoE++ (up to 90 W/123 W) standards.

Figure 5 Power levels supported by ADI PoE PSE

Figure 6 ADI LTC4279

The LTC4279 supports 123W output and is in full self-starting mode by default.

Figure 7 Simplified schematic of the LTC4291-1 and LTC4292 PoE++ 4-port PSE chipset

As shown in Figure 7, users can communicate with the LTC4291-1/LTC4292 PSE chipset through the I2C interface and select one of four PSE operating modes (automatic, semi-automatic, manual, or shutdown) according to different applications; the LTC4291-1 provides a PSE host isolated digital interface, while the LTC4292 provides a high-voltage Ethernet interface. Up to 6 expensive optocouplers and 1 isolated power supply can be replaced with cheaper and more reliable 10/100Mbps Ethernet transformers; the automatic mode can be configured by setting AUTO high.

Figure 8 Industrial PSE switch using the LT4290A/LT4271 chipset

The industrial PSE switch uses the LT4290A/LT4271 chipset, has 6 10/100/1000M RJ45 ports, and supports IEEE802.3 bt protocol. Ports 1-4 support ultra-high power output of 71W, and are backward compatible with the IEEE 802.3af/at PoE international standard. The single-port PoE power is up to 95W; the industrial PSE switch can automatically detect and identify the power receiving devices that meet the standards, and power them through CAT5 or higher-level network cables, and power high-power wireless APs, network dome cameras, high-power PoE lighting, industrial sensors and other PoE terminal devices.

PoE Lighting Node--Powered Device (PD)

ADI offers LTPoE++, PoE+, and PoE standards with PD controllers with integrated isolated switching regulators; power levels range from 2 W to 90 W.

Some PD devices integrate DC-DC controllers (LT4295/LT4275A shown in Figure 8), which can simplify the design for some specific applications.

For those LTPoE++ PD designs that need to be able to support auxiliary power, the PD can optionally be powered by a power adapter, and the LT4321 shown in Figure 12 is compatible with PoE, PoE+, and LTPoE++™.

PoE Lighting nodes can share data collected through external sensors of LED lamps (such as light environment, human infrared sensing, temperature and humidity, air quality, etc.), which can be used in various aspects from automatic adjustment of air quality and comfort to health and safety threat detection, crowd control and optimized operations.

Figure 9 PoE Lighting Node Product Specifications

Figure 10 PoE Lighting Node

PoE Lighting interface--Industrial Ethernet/RS485

ADI also offers the Industrial Ethernet PHY ADIN1300 (rate range 10 Mbps to 1 Gbps) and ADIN1200 (rate range 10 Mbps to 100 Mbps).

Figure 13 ADIN1200/ADIN1300

Summarize

The advantages of PoE lighting far exceed the energy saving, environmental protection and control capabilities of simple LED. As an IP-based device integrated into the network, PoE lighting can be controlled and managed from anywhere through software and integrated with other network application functions.

Shijian can provide a complete ADI PoE power supply solution (PSE+PD+Bridge Controller), while combining advanced and mature sensor technology to establish an ideal network-based platform.