Power over Ethernet (PoE) switches have gained significant popularity as a practical solution for businesses seeking to conveniently deliver power and data through a single connection. In this comprehensive guide, we will delve into the various types of PoE switches, highlight their advantages and applications, and provide insights on selecting the most suitable PoE switch to meet your specific requirements.

What is a PoE Switch?

A PoE switch combines the functionalities of a switch and a power source into a single device. Equipped with multiple Ethernet ports, these switches facilitate seamless connections with various devices such as VoIP phones, wireless access points, and IP cameras. By integrating power delivery capabilities, PoE switches eliminate the need for separate power cables, streamlining installations. These switches prove particularly beneficial in network deployments where power outlets are limited or in scenarios where devices are situated in challenging-to-access locations.

PoE switches leverage the power over Ethernet (PoE) technology, enabling the simultaneous transmission of data and electrical power through Ethernet cables. This innovative technology employs a combination of power sources and power injectors to deliver power to connected devices. Acting as intermediaries between the power source and the devices, power injectors handle the transmission of both data and power, ensuring efficient operation. Also Check- PoE switch

 

Types of PoE Switches

When selecting a PoE switch, it is vital to familiarize yourself with the various types available. There exist two primary categories of PoE network switches:

The Unmanaged PoE Switch

Designed for simplicity and ease of use, the unmanaged PoE switch offers a plug-and-play solution that suits smaller setups. It requires minimal configuration and is user-friendly. However, it lacks extensive customization options, management features, and advanced security capabilities. Consequently, it is best suited for applications with uncomplicated network requirements, such as home networks or small-scale environments comprising fewer than 5-10 computers.

The Managed PoE Switch

Engineered to deliver enhanced control and comprehensive network management, managed PoE switches excel in scenarios that demand advanced functionality. With their robust security features and extensive configuration options, they prove ideal for applications like enterprise networks, data centers, and large-scale surveillance systems. These switches offer features such as VLANs (Virtual Local Area Networks), QoS (Quality of Service), port mirroring, and heightened port security, catering to complex networking requirements.

Advantages of PoE Switches

Given how PoE switches work, the benefits of PoE switches are obvious.

Simplified Installation: PoE network switches are known for their user-friendly installation and configuration. With plug-and-play functionality, these switches eliminate the need for complex wiring or intricate setup procedures. Built-in features like port mirroring, VLANs, and QoS further simplify network management tasks, enhancing overall operational convenience.

Cost Efficiency: PoE switches exhibit remarkable energy efficiency. By intelligently delivering the precise power required for each connected device, they eliminate the need for oversized power supplies. This efficient power allocation not only reduces energy consumption but also contributes to long-term cost savings, making PoE switches a financially advantageous choice.

Enhanced Flexibility: The ability to power devices through PoE enables easy relocation to areas without available power outlets. This flexibility allows PoE switches to be conveniently placed in challenging-to-reach locations or areas distant from power sources. Security cameras, for instance, can be strategically installed in optimal positions, regardless of the availability of nearby power outlets.

Future-Proofing: With the rapid growth of the Internet of Things (IoT) industry, PoE switches provide future-ready infrastructure. By incorporating PoE switches into your network, you can seamlessly accommodate the increasing number of devices designed to leverage this technology. This scalability ensures long-term compatibility and positions your network for seamless integration with emerging IoT devices.

 

PoE Switch Applications

This rapid expansion of network-connected devices means that PoE technology and PoE switches will grow in importance to most networking infrastructures. While PoE switches have numerous applications, we mainly discuss the three most common application scenarios.

• VoIP Phones: VoIP phones are PoE devices, with PoE allowing for a single connection to the wall socket and the ability for remote powering down

• IP Cameras: Security cameras can be connected to PoE switches to enable fast deployment and simple repositioning.

• Wireless: Many wireless access points are PoE compatible. Thus, PoE switches allow for easy relocation and remote positioning.

• Smart Home Automation: LED lighting, heating and cooling systems, appliances, voice assistants, and electric car charging stations.

How to Select the Right PoE Switch

When selecting a PoE switch, it is important to consider your application requirements, the features and limitations of the PoE network switch. Of course, the power requirements of connected devices are also important. Some PoE network switches are designed to power devices that require up to 30 watts, and some are even designed for power devices that require up to 60 watts.

Features of PoE Switches to Consider

In addition to the type of switch and power requirements, there are a number of features to consider when selecting a PoE switch. These features include port speed, port count, port types, PoE budget, power savings, and port security.

• Port speed: Maximum speed a port can achieve. It is important to choose a switch with a port speed that can support the connected devices. The port count is the number of ports available on the switch. It is important to choose a switch with enough ports to accommodate all of the connected devices.

• Port type: Common port types include RJ45, SFP, and SFP+. It is important to choose a switch with the right port type for connected devices.

• PoE budget: Maximum amount of power that can be allocated to connected devices. It is important to choose a switch with a PoE budget that can accommodate all of the connected devices.

• Power savings: Designed to conserve energy by automatically turning off unused ports. This can help to reduce energy costs. 

• Port security: Designed to protect connected devices from unauthorized access.

Limitations of PoE Switches

Nonetheless, there are some limitations to PoE variation that you should be aware of:

• Restrictions on distance: Typically, PoE switches can transmit over Ethernet up to a distance of up to 100 meters. The 100-meter distance restriction presents a challenge for large campuses, restaurants, and businesses implementing PoE. However, there are still devices like power extenders and powered fiber cables that can be used to extend the PoE range.

• Power: If you require high power over poe networks, you must ensure that the power capacity of your PoE switches meets your requirements due to the power limitation imposed by PoE standards and Wattage.

 

FAQs about PoE Switch

Q: Non-PoE vs. PoE Switch: How do they differ?

A: Non-PoE switches cannot deliver power to connected devices, necessitating the use of midspan power sourcing equipment (PSE), such as a PoE injector. This setup adds power while transmitting data to powered devices (PDs). In contrast, PoE switches offer a simpler solution, directly delivering power and data to PDs with just a network cable and a power cable.

Also Check- PoE vs PoE+ vs PoE++ Switch: How to Choose?

 

Q: Do PoE Switches Require Special Cables?

A: No. The Ethernet cables that should be used for PoE network switches primarily depend on the data rate of the PoE port; for instance, Cat3 or better cables can be used for 10/100M; Cat5/Cat5e/Cat6 cables are required for 1000M. In the future, Cat6a or higher cables may be required for the installation of 2.5G/5G/10G PoE devices.

 

Q: Active vs Passive PoE Switch: Should I Choose Active or Passive PoE Switches?

A: Active PoE network switch complies with standard PoE. On the contrary, passive PoE network switch does not adhere to any IEEE standard. There are many ways that active and passive PoE switches differ from one another, like how the PoE power supply pinout looks and whether or not they support Ethernet.

 Also Check- Active vs. Passive PoE Switch: Which Should We Choose?

 

Q: Can the PoE Switch be used with a computer or other non-PoE devices? And will a PoE switch harm devices that do not use PoE?

A: Yes, a PoE switch can be used with non-PoE devices like computers. The switch automatically detects whether a connected device is PoE-compatible and will only supply power to PoE-enabled devices. So, it won't harm non-PoE devices; they just won't receive power through the switch.

 

Q: Is it possible to connect two PoE switches?

A: You could, yes. The PSE only supplies PD with power when it determines that the device can handle it. As PSEs, the two PoE switches will only be used for data communications.

 

Q: What is the maximum transmission distance of PoE? How to extend the transmission distance of PoE?

A: Whether using IEEE 802.3af (PoE) or 802.3at (PoE+), data and power transmission are limited to a distance of 100 meters over Ethernet cables in standard PoE. Media converters and PoE extenders, for example, can extend the range to up to 300 meters if you want to increase the maximum distance.

Conclusion

PoE switches are an effective solution for businesses looking to provide power and data over a single connection. They can simplify installation, reduce clutter, and improve energy efficiency. When selecting a PoE network switch, it is important to consider your application requirements, the power requirements of the connected devices, and the features of the switch. It is also important to consider the cost and long-term cost savings of using a PoE network switch.

If you are looking for a reliable and cost-effective PoE switch, check out Linovision PoE Switches.

With the wide application of VoIP phones, IP cameras, and wireless access points, Power over Ethernet (PoE) has made great strides in recent years. And PoE network is expected to expand rapidly in the future due to the increasing number of IoT applications and smart device deployments and newly ratified standards designed to support more smart devices. In this article, we will provide an introduction covering various aspects of PoE such as PoE wiki, PoE standards, PoE types, PoE classes, and PoE applications.

What Is Power over Ethernet (PoE)?

PoE is a networking technology that can transmit both data and power over one single standard Ethernet cable. It allows us to use network cables such as Cat5/Cat5e/Cat6/Cat6a cables to provide data connections and electric power to wireless access points, IP cameras, VoIP phones, PoE lighting and other powered devices (PDs). With the use of PoE technology, we can easily deliver power to indoor or outdoor PDs without the need to install additional electrical infrastructure or to deploy power outlets at every endpoint.

Benefits of PoE Network—Why Use Power over Ethernet?

Besides the above-mentioned benefits, there are several more appealing reasons for adopting PoE in networking.

Time & Cost Saving: By using PoE in the network, we do not need to deploy electrical wiring and outlets for terminal PDs. This will help to save much power cabling cost especially when there are lots of PDs in the network. Furthermore, there is no need to hire a qualified electrician for the PoE network, so you may also save both time and money on electrical installations.

Flexibility: Since Ethernet network cables are easier to deploy than electrical ones, PoE networking allows us to install PDs nearly anywhere rather than near the electrical outlets. This offers a ton of flexibility for setting up and repositioning terminal devices.

Reliability: PoE power comes from a central and universally compatible source rather than a collection of distributed wall adapters. It can be backed up by an uninterruptible power supply (UPS) or controlled to easily disable or reset devices. By doing so, the PDs will run as usual even though Power Sourcing Equipment (PSE) breaks down.

Evolutionary Path of the Power over Ethernet (PoE)

Institute of Electrical and Electronics Engineers (IEEE), Cisco, and the HDBaseT Alliance have released several standards to define PoE. These standards include IEEE 802.3af, IEEE 802.3at, IEEE 802.3bt, Cisco UPOE, and Power over HDBaseT (PoH).

PoE Types

Due to different classification standards, PoE can be divided into different types. Currently, there are 4 PoE types based on IEEE PoE Standard: Type 1(IEEE 802.3af), Type 2(IEEE 802.3at), Type 3(IEEE 802.3bt), and Type 4(IEEE 802.3bt), as shown in the following chart.

PoE vs. PoE+ vs. PoE++ (UPoE )vs. PoH

PoE (IEEE 802.3af), also known as PoE type 1, provides up to 15.4 watts of power per port and is used for devices like IP phones and cameras. PoE+ (IEEE 802.3at), PoE type 2, offers up to 30 watts and powers devices like PTZ cameras. PoE++ or UPoE (IEEE 802.3bt), also referred to as PoE type 3, delivers up to 60 watts and 100 watts, PoE type 4, per port for high-performance devices. Power over HDBaseT (PoH) enables power and data transmission for AV equipment over a single cable. The figure below illustrates the common applications of different PoE types for your reference.

PoE Classes

Power over Ethernet (PoE) classes define standardized power levels for different network devices. These classes ensure compatibility between Power Sourcing Equipment (PSE) and Powered Devices (PD).

The classes, ranging from Class 1 to Class 8 as the above chart shows, correspond to specific IEEE standards, indicating the maximum power output of the PSE and the maximum power input of the PD. Let’s delve into more details about each class:

Class 1 is suitable for low-power devices such as IP phones, voice-over-IP (VoIP) devices, and basic sensors.

Class 2 is intended for devices that require slightly higher power, including wireless access points, small IP cameras, and IP intercom systems.

Class 3 is commonly used for devices that require moderate power, such as larger IP cameras, point-of-sale systems, and access control devices.

Class 4 provides increased power delivery capabilities and is suitable for power-hungry devices like pan-tilt-zoom (PTZ) cameras, video phones, and thin clients.

Class 5 introduces the support for four pairs of Ethernet wires, enabling higher power transmission. It is designed for devices with more demanding power requirements, including advanced PTZ cameras, multi-channel wireless access points, and small LED lighting systems.

Class 6 provides increased power delivery capabilities beyond the previous classes. It can support devices like high-power pan-tilt-zoom cameras, multi-radio wireless access points, and small LCD displays.

Class 7 offers even higher power capabilities introduced with the IEEE 802.3bt standard. It is suitable for devices like high-performance access points, large displays, and thin clients requiring substantial power.

Class 8 represents the highest power class defined by current PoE standards. It is designed for power-hungry devices such as video conferencing systems, advanced lighting systems, and digital signage

It’s important to note that the power levels specified for each class represent the maximum allowable values, and the actual power delivered or consumed by the PD may vary based on its specific power requirements and negotiation with the PSE. Besides, understanding PoE classes allows network administrators to ensure that the power requirements of their devices align with the capabilities of their PoE infrastructure, ensuring proper operation and avoiding potential power supply issues.

Passive PoE vs. Active PoE

Power over Ethernet can also be divided into passive PoE and active PoE in general. Active PoE is the standard PoE which refers to any type of PoE that negotiates the proper voltage between the PSE and the PD device. Passive PoE is a non-standard PoE technology. It can also deliver power over the Ethernet line but without the negotiation process.

How to Add PoE to Your Network？

The PoE supplied in the network generally comes from three different sources: PoE switch, PoE injector, and PoE splitter. The PoE switch is the easiest way to power up the PDs. You only need to run Ethernet cables from a PoE network switch port to the terminal PoE device. A PoE injector is used when there is no PoE switch in the network. It has an external power supply and is responsible to add power to data that is coming from a network switch that is not PoE-capable. PoE splitters also supply power, but they do so by splitting the power from the data and feeding it to a separate input that a non-PoE-compliant device can use. It is commonly used for deploying remote non-PoE devices with no nearby AC outlets in the network.

Common FAQs on PoE Network

Q: What is the voltage of Power over Ethernet?

A: Power over Ethernet is injected onto the Ethernet cable at a voltage between 44v and 57v DC, and typically 48v is used. This relatively high voltage allows efficient power transfer along the cable, while still being low enough to be regarded as safe.

Q: What data speed does PoE offer?

A: Generally, PoE can deliver data rates at 10/100/1000Mbps over Cat5, Cat5e and Cat6 cables. Now thanks to the widespread IEEE 802.3bt PoE standard and PoE++ technology, PoE is able to deliver speeds of 2.5 Gbps to 5 Gbps over 100m and reaches 10 Gbps in recent times.

Q: Are there any limitations of PoE network?

A: Yes, PoE network does have some pesky limitations. First, it has a restricted reach of 328 feet (100 meters) which limits the viable locations where users can operate a remote IP-enabled device. Second, a single PSE such as a PoE switch usually connects to multiple PDs. If the PSE broke down, all the PDs will stop working. Therefore, it is important to buy qualified switches from a reliable supplier. In addition, you may also consider connecting the PSE to an uninterruptible power supply system.

Q: What are PoE midspan and PoE endspan?

A: The PoE midspan is usually a PoE injector that serves as an intermediary device between a non-PoE switch and the terminal PoE-capable powered device. A PoE endspan, which is commonly called the PoE network switch, directly connects and supplies both PoE power and data to a PD. PoE endspan provides power over the data pairs, also known as PoE Mode A. PoE midspan provides power using the pins 4-5 and 7-8, also known as PoE Mode B.

Introduction:

In a PoE power supply system, the essential components are the Power Sourcing Equipment (PSE), the Powered Device (PD), and the PoE cables. When issues arise with PoE, it often manifests as the PoE switch failing to provide power, resulting in the powered devices ceasing to function. These failures can stem from various factors, including hardware and software-related issues. This article aims to help you accurately identify the root causes of PoE errors and minimize troubleshooting time. We will discuss three common PoE faults and provide troubleshooting methods for Power over Ethernet.

PoE Error 1: PoE Switch Fails to Provide Power

One of the most frequently encountered PoE errors is when a PoE-powered device (PD) fails to boot up due to issues with PoE components or incorrect configuration commands. Follow the steps below to address this problem:

Step 1: Verify PoE IEEE Standards and Power Modes of PSE and PD

Ensure that both the Power Sourcing Equipment (PSE) and PD comply with PoE IEEE standards. It's important to note that non-standard PoE switches, also known as passive PoE switches, deliver power over Ethernet lines at a fixed voltage, regardless of whether the terminal device supports PoE or not. Improperly prepared passive PoE switches may damage the terminal devices. Additionally, the power modes of PSE and PD can contribute to PoE faults. There are three PoE modes: Alternative A, Alternative B, and 4-pair delivery. If a PD supports only PoE mode B power delivery while the PoE switch is based on Alternative A, they will not work together. Confirm the power supply modes of PSE and PD with the vendor.

Step 2: Check the PoE Cabling

Mismatched Ethernet cables and PoE ports can result in network failures. Furthermore, PoE failures can occur if the cable has hardware faults or fails to meet necessary standards. Therefore, it's highly recommended to ensure that the Ethernet cable supports PoE and is functioning properly before connecting the powered device.

Step 3: Verify Sufficient PoE Power

In theory, the PSE device interface can automatically detect the connected PD. If the power supply is insufficient, the PD will not receive power. Make sure that the power required to run the PDs does not exceed the power budget of the PoE network switch. If a PSE detects that the PD's power class falls within its capacity, it will power on the PD.

Step 4: Check PoE Power Management Configuration

Verify whether the switch interface has automatic PoE power management configuration enabled. If not, you will need to manually deliver PoE power to the connected PDs through the PoE network switch interfaces.

PoE Error 2:  Intermittent Power Loss or Reloads of a PoE PD

What if a functioning PD experiences intermittent power loss or reloads? These situations may arise due to insufficient power supply and poor-quality PoE cables.

Step 1: Check Whether PoE Power Is Sufficient

A PD can power off or reload intermittently if the PSE's output power is insufficient to support all PDs operating at full power consumption. This can cause the PoE switch to fail to provide power. Take IP cameras as an example. During testing of extended functions such as Pan-Tilt-Zoom, heaters, or wipers, the PD may consume significantly more power than during normal operation. If no additional power is available, the camera may get stuck in a continuous boot cycle. To troubleshoot this PoE fault, measure the power requirements of the IP camera during startup and use an appropriate PSE to provide sufficient power.

Step 2: Check the PoE Cabling

If the Ethernet cable used in a PoE link is over 100 meters or has power loss due to the material and resistance of the cable itself, the PD would not get sufficient power, causing issues like network failure or latency. If the cables are not qualified, it will lead to PoE faults as well.

PoE Error 3: Inconsistent Powering of PDs on the Same PSE

If some PDs are receiving power while others connected to the same PSE are not, follow the tips below:

Step 1: Check if PDs Are Available on Other Ports

Determine whether the issue lies with specific ports on the PSE. Disconnect the PoE cable between the Ethernet switch port and the non-powered PDs. If the PDs receive power when connected to other PoE ports, it indicates a problem with specific ports. Verify if the port is shut down or error-disabled using configuration commands. If so, enable PoE functions through the appropriate command.

Step 2: Check the PoE Power

If newly added PDs to PSE ports are not powering on, it may indicate that the PoE switch's power budget is depleted. Ensure that the remaining PoE power in the PSE is equal to or greater than the maximum output required by the connected PDs. Additionally, limit the per-port current to safe levels and consider using additional PSE devices if necessary.

PoE Error 4: PoE Cameras Not Powered

If your camera cannot be powered on while using a PoE Switch or PoE injector, you may follow the tips below to solve your problems.

Step 1: Verify Camera Compatibility with PoE Switch/Injector

Check the compatibility requirements of your camera with the PoE switch or PoE injector. Ensure that the specifications of the PoE switch or injector align with the camera's requirements.

Step 2: Check if the Camera Is Fully Connected to the PoE Switch/PoE Injector

Inspect the PoE port lights on thePoE switch or PoE injector to confirm if the camera is fully connected. If the lights are not illuminated, try plugging the camera into other ports and using a different Ethernet cable. Also, check if the PoE port of the switch is damaged or rusty. You can test this by connecting the camera to other functioning PoE ports.

Step 3: Check if the PoE Module of the Camera Gets Power

If the camera's PoE module is not receiving power, use a DC adapter with the correct output voltage to power the camera. Make sure the DC/AC adapter is available and compatible. Typically, the adapter has an indicator light that indicates the presence of power. Some IP cameras support both DC and AC power supply ports, such as DC12V/2A and AC 24V/3A. Verify that the adapter's specifications match those of the camera.

Conclusion