Power over Ethernet (PoE) technology allows Ethernet cables to deliver both data and power to devices like wireless access points, IP cameras, and VoIP phones. This removes the need to have separate power cables for each device, making installation easier and less expensive. However, not all Ethernet cables are capable of safely and reliably transmitting power in addition to data. When building a PoE network, it’s important to choose the right type of Ethernet cabling to avoid performance issues or equipment damage.
In this buyer’s guide, we’ll walk through the key factors to consider when selecting Ethernet cable for your PoE installation. We’ll explain the different categories of PoE and the cable specifications required to support each level of power delivery. We’ll also discuss the importance of using solid copper conductors rather than copper clad aluminum (CCA) for PoE applications. Whether you’re cabling a small office or outfitting a large enterprise network, this article will arm you with the knowledge to select the appropriate PoE-ready Ethernet cables and connectors to build a robust, high-performing wired network.
The Different PoE Categories and Required Cable Specifications
The IEEE 802.3 standard defines several classes of PoE to deliver increasing levels of power over Ethernet cables:
- PoE (802.3af) – Delivers up to 15.4W of DC power over Ethernet. Requires Category 5 or higher cable with 2 pairs (4 conductors). The resistance must not exceed 20 ohms per conductor, allowing operation at distances up to 100 meters.
- PoE+ (802.3at) – Also known as PoE Plus, this provides up to 30W of power. A minimum of Category 5e cable is specified, with 2 pairs of 24 AWG copper conductors. Cable runs are supported up to 100 meters distance.
- PoE++ (802.3bt) – Released in 2018, this doubles the power to 60W over 4 pairs of copper cabling. Category 5e, 6, or 6A cables with conductor sizes of 22-26 AWG may be used. At least 2 pairs must have 20 ohms or less dc loop resistance for 100 meter cable runs.
- UPoE (Proprietary) – Some vendors offer Ultra PoE with capacities over 60W. This may use all 4 pairs for power, with heavy 22 AWG conductors or thicker. Exceeds the official PoE standards and requires compatible hardware. Enables extended transmission distances.
As PoE power levels increase, higher performance Ethernet cable is required. For any PoE installation, it’s critical to use good quality copper cabling and connectors rated to handle the electrical loads. Going beyond standard PoE requires professional grade cabling with robust shielding and conductors. This ensures safe, efficient power delivery across the network.
Cat5e, Cat6a, and Cat7 Ethernet Cable Specifications for PoE Networks
Category 5e (Cat5e) Ethernet Cable
Category 5e (Cat5e) cable is the minimum standard required for Gigabit Ethernet networks. For PoE applications, Cat5e provides support up to the PoE+ standard of 30W power delivery. It uses 4 twisted pairs of copper conductors at 24 AWG gauge. The maximum conductor resistance is 20 ohms per 100 meters to allow for voltage drop. Cat5e has enhanced shielding compared to Cat5 and is rated for speeds up to 1Gbps at distances up to 100 meters.
Category 6a (Cat6a) Ethernet Cable
Category 6a (Cat6a) cable offers higher performance and is suited for 10Gbase-T networks. It supports the full PoE++ power level of 60W. Cat6a uses thicker 23 AWG copper conductors, which allows for lower resistance of 17 ohms per 100m cable run. The twisted pair design helps minimize crosstalk and electromagnetic interference. Cat6a enables 10Gbps Ethernet networks over distances up to 100 meters.
Category 7 (Cat7) Ethernet Cable
Category 7 (Cat7) is rated to reach speeds up to 10Gbps at significantly longer distances up to 600 feet. The conductor gauge can range from 22-24 AWG and adds additional shielding compared to Cat6a. This enhances noise rejection and makes Cat7 well suited to challenging industrial environments. The thicker conductors also make Cat7 capable of handling Ultra PoE power levels exceeding 60W. Overall, Cat7 offers the highest performance PoE cable option.
When planning a PoE enabled network, choosing the right category of high quality Ethernet copper cabling tailored to your speed, power, and distance requirements is crucial. This will provide a future-proof foundation that can evolve with emerging PoE capabilities and devices.
What To Consider When Selecting Ethernet Cable for PoE Installation?
- PoE standard support – The category of PoE will determine the power levels supported. Select cabling that meets the specifications for the PoE standard you are using (e.g. PoE, PoE+, PoE++).
- Cable performance – Choose cables with high-quality conductors and shielding to minimize noise, interference, and power loss over long distances. Look for features like twisted-pair construction and foil or braided shields.
- Conductor size – Larger conductors typically allow for higher power capacity and less voltage drop. 24-26 AWG is common for PoE.
- Conductor material – Copper conductors are required. Solid copper is better than copper-clad aluminum (CCA) for PoE.
- Ethernet speed rating – Match the cable category/class to the Ethernet speeds required (e.g. Cat5e for 1Gbps, Cat6/6a for 10Gbps).
- Wattage rating – Verify the cable is rated to safely handle the full PoE power levels required by connected devices.
- Flammability rating – Plenum-rated cables are flame retardant for running cable through walls and ceilings.
- Environmental factors – Consider if the cables will be exposed to moisture, extreme temperatures, chemicals, etc.
- Connector type – Choose compatible copper Ethernet connectors (RJ45, GG45, TERA) rated for PoE.
- Cost – Higher performance cables typically have a higher cost. Balance requirements with budget.
Why Solid Copper Is Preferred Over Copper Clad Aluminum (CCA) for PoE Applications?
Solid copper conductors are strongly preferred over copper clad aluminum (CCA) for Power over Ethernet applications for several important reasons:
Higher current capacity: Solid copper has approximately 10-15% greater ampacity (current carrying capacity) versus the same gauge CCA wire. For example, 24 AWG solid copper has a maximum current of 1.61A, versus 1.4A for 24 AWG CCA. This provides headroom for the continuous power loads in PoE circuits.
Lower resistive loss: The resistivity of copper is 1.72 microohm-centimeters, whereas aluminum is 2.82 microohm-centimeters. This translates into substantially lower resistance and less voltage drop on copper wire runs. Voltage drop can impair PoE device operation.
No oxidation: Copper forms a protective patina when exposed to air, while aluminum oxidizes. The aluminum oxide layer causes increased resistance and inferior electrical connections. Copper maintains conductivity over the life of the cabling.
More bendable: CCA has a stiff aluminum core that is brittle when bent repeatedly. Copper wire is soft and flexible, allowing easier PoE installs in crowded conduits and spaces.
Higher temperature rating: Copper is rated for continuous use up to 167°F (75°C), while CCA cable insulation limits operation to just 140°F (60°C). PoE cables may be subjected to temperature elevations.
For critical PoE networks like securing buildings or providing VoIP telephone service, the enhanced electrical performance and reliability of solid copper cabling is an important safeguard. The cost savings of lower grade CCA wire is not worth the compromise for such business-critical applications.
How To Identify Authentic and Quality Ethernet Copper Cabling for PoE Networks?
Here are some tips to identify authentic and quality Ethernet copper cabling for PoE networks:
- Examine the jacket markings: Authentic cables are clearly stamped with ratings like Category 5e, 6a, etc along with the manufacturer’s name. Look for quality brand names known for cabling such as Belden, CommScope, or Mohawk.
- Check conductor size: Strip back some sheathing to inspect the wire gauge. Cat5e should have 24 AWG, Cat6a 23 AWG, and Cat7 22-24 AWG sized conductors. Larger is better for PoE power capacity.
- Verify performance ratings: Quality cable meets standardized specs like UL or ETL for things like flammability, which are printed on the jacket. Cat5e is typically rated for 1Gbps speeds up to 100m, Cat6a for 10Gbps to 100m.
- Look for solid conductors: Stranded wire contains small threads of copper, while solid core has a single conductor. Solid increases density and power capacity. Avoid cheaper CCA cables.
- Examine connector pins: Quality connectors will have copper-alloy pins plated in gold or tin. Pins should be firmly crimped to conductors with no gaps or imperfections.
- Test cable functioning: Use a cable tester to validate PoE power and data transmission works error-free over the rated length when installed. Also check for pin defects.
Inspected thoroughly, authentic, high-performance copper cabling for PoE will demonstrate consistent quality materials, construction standards, and electrical capabilities. Though more costly, this provides assurance of long-term reliability.
Final Thoughts
When designing and installing a Power over Ethernet network, selecting the proper Ethernet cable is one of the most important decisions. The cable carries both network data and power to devices, so it needs to meet electrical and performance requirements. By understanding the different categories of PoE, conductor specifications, and cable properties, you can ensure you choose a cable that will safely and reliably support the power loads demanded by PoE devices across your network infrastructure.
The good news is that as PoE standards have evolved, Ethernet cabling capabilities have advanced as well. With the right Cat5e, Cat6a, or Cat7 Ethernet cable from a reputable manufacturer, you can deploy a high-speed, high-power PoE network with confidence. Using quality solid copper conductors and connectors rated for PoE will provide headroom to support devices today and into the future.
While PoE cabling represents an additional upfront investment compared to non-PoE networks, the long-term savings from reduced installation costs and easier moves, adds, and changes are substantial. PoE makes deploying devices like wireless APs, VoIP phones, and IP cameras plug-and-play simple. By taking the time to understand your requirements and match them to the appropriate cabling, you’ll lay the foundation for a PoE network that can evolve to meet your needs.
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