Power over Ethernet for industrial applications

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Power over Ethernet for industrial networks

In this post, we explore the benefits of Power Over Ethernet (PoE) for industrial networks. Power over Ethernet (PoE) technology in Ethernet switches can provide power to equipment used at the edge of networks such as cameras and access points. Since a single cable delivers power and data simultaneously, PoE installation is less expensive than traditional wiring. Learn what other benefits PoE switches offer in an industrial network, as well as how smart PoE is, and what the difference between PoE and PoE+ is.

What is Power over Ethernet (PoE)?

Power over Ethernet technology provides power to equipment such as sensors, IP cameras, and access points using a single Ethernet cable. With an industrial PoE switch, complexity of a network can be reduced with one cable for both power and connectivity. Using this technology, a device can run solely on the power it receives through the Ethernet cable, eliminating the need for a separate power source.

PoE switches built for industrial environments are specifically designed to be capable of withstanding extreme temperatures, humidity and electrical environments. In contrast, non-industrial Ethernet switches typically perform better when kept in a temperature-controlled environment. Industrial switches are also vibration and shock-resistant, making them ideal for harsh work environments such as those found in railway trackside, marine, oil & gas and mining. The right PoE switch will keep your network operational even under adverse conditions.

Illustration exemplifying the flexibility that comes with a PoE switch

What are the benefits of PoE?

In an industrial application, PoE has many benefits, including:

Ease of Installation and flexibility

Since PoE eliminates the need for each device to be tied to an electrical outlet, you have greater flexibility when installing a device and can place it wherever it is needed. PoE can keep installations much more simple and makes networks more efficient.

Cost savings

Since a single cable delivers both power and data simultaneously, PoE installation costs are lower than those of traditional wiring. With a single source of power for each end device, installation is simpler and less hazardous than with multiple adapters and outlets.

PoE enables outdoor installations without the need for additional electrical infrastructure, therefore leading to lower installations costs and possible network expansion.

Scalability

Once the PoE Switch is installed and operational, networks can easily be expanded with PoE and non PoE devices, reducing the requirement for additional expertise on site. By repurposing legacy systems and not relying on outlets, new network connections are easily installed. PoE networks can be scaled up easily to add more devices in additional locations when required.

Remote Installations

Thanks to PoE networks, devices can now be installed in locations that were previously difficult to access because local power is no longer required. Before PoE, an independent power supply, along with safety equipment, was required when a device required power in a remote location. With PoE, as the power source is supplied by the PoE Switch, like the Lynx 3510 PoE, expansion and installation are much easier. Ethernet cables can carry 30W of power up to 100m, eliminating the need for unnecessary installation and simplifying maintenance.

What is the difference between PoE and PoE+

PoE (802.3af) and PoE+ (802.3at) are two independent standards. PoE+ is an upgrade of PoE that provides more power to end devices. The PoE limit has historically been 15.4 watts, which makes it difficult for devices that consume more power, such as CCTV cameras, IP cameras, and video IP phones to be installed with ease. With PoE+, devices with higher power requirements can receive up to 30 watts. There is no shortage of power in the Lynx-3500 series as it features 240 watts of total power.

Power being transferred over an Ethernet cable.

Power being transferred over an Ethernet cable

How smart is PoE?

All PoE devices have a power budget, which means that if too much power is drawn at once, some limitations may occur. If this is the case, a device can prioritise which ports receive power, and which do not. This is known as PoE Priority and can be configured in three levels, Low, High and Critical. In the rare case, the PoE device will reduce the power output to devices configured as low and high. This will ensure that devices recognised as critical are always supplied with power. This option is configurable, however, it is also enabled by default on specific ports.

Fortunately, the Lynx 3510 PoE offers 240W of power margin, which is more than enough for many PoE installations.