How to test your Ethernet Cables for PoE Compatibility

Published on Updated on December 05, 2023

PoE Ethernet cables (Power of Ethernet) are getting more and more popular every day. As consumers learn more about what these cables can do and how they work, and businesses and industries take increasing advantage of the added flexibility that comes with transmitting power and data in a single cable, PoE Switches are also getting more important for everyday life. However, not all cables can support transmitting both power and data, and trying to use a cord that isn’t designed for this use can quickly damage the cable, and potentially damage the connected equipment at the same time. At best, the cord simply won’t do what you’re asking it to. At worst, it will break, damage connections, and cause other problems. The more often you try to use an incompatible cable, the greater the risk of damage.

If you aren’t sure whether a given ethernet cable supports PoE, it’s important to test the cable before attempting to use it. Here’s how.

Ethernet Cables and PoE Compatibility

Steps for Testing Ethernet Cables for POE Support

To test your ethernet cable you will need a standard DSX Cable Analyzer

  • Standard Cable Testing
    The first step is to make sure your ethernet is working properly as an ethernet cord. Unused cords might already be faulty, damaged, or otherwise non-functional before you get started. So making sure it can pass standard testing will help make sure the ethernet cord is working properly. You'll just need to run a standard TIA/ISO field test on the cord with the DSX cable analyzer. It will give you a pass/fail on that test. Assuming you get a pass, it's time for test 2.
  • Test Cable Resistance
    In addition to passing standard ethernet tests, PoE cords need to also pass a resistance test. The greater the resistance the cable offers, the more voltage you’ll need to provide to get a current running through the cable. Standard field tests don’t normally test for resistance, which is why you’ll also need to run the +PoE test on the cord.

    There are 4 levels of resistance required for a PoE pass, and the different ratings are between PoE and PoE++, with two different levels of PoE++ providing either 51W or 71.3W. It’s important to match the PoE pass level to the devices you’re planning to connect. Look up what PoE type you need for your intended purpose before connecting your ethernet cord.

    Using the PoE+ test, you’ll be able to determine whether your ethernet cord supports PoE use, and what PoE type it is. You should only use PoE cords of the right type for your intended use, otherwise, you may have an imbalance, which can also cause a range of problems from cord failure to damaging one or both connected devices.
PoE Switches


PoE testing is easy, and effective, and can save you a lot of money in lost time and potential damage to your equipment. Don't risk causing more problems by using the wrong cord. If you don't already know a cord's PoE compatibility and type, test it. If you do know the cord's PoE compatibility and type, but are worried it might have been damaged for any reason, test it. Thankfully, with the right equipment, the process is simple and the results are reliable. VERSITRON Inc. offers wide range of PoE Products that meet your requirements. Please give us a call (1-800-537-2296) or open a chat with any questions. We would be delighted to speak with you!

Rich Tull

Rich Tull
R.W. Tull is the President of Versitron, a leading technology company specializing in data communication and networking solutions. With expertise in Guiding network switches and media converters, R.W. Tull has played a pivotal role in driving Versitron's success. His deep understanding of these technologies has enabled the company to provide innovative and reliable solutions to clients. As a visionary leader, He ensures that Versitron remains at the forefront of the industry, delivering cutting-edge networking solutions that enhance data communication efficiency.
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