PoE Voltage Tester

[MrSurly]

A question about testing PoE: Yes, I have DVMs and of course I can make a quick connector to try to read voltage at an injector or switch, but since the voltage and current (depending on the particular PoE standard) relies on a software negotiation between devices, I'm certain that the DVM can't see the full story. Are there tips for checking the voltage with a DVM if that's all you have handy? Minumum voltage that should always be present? max voltage? Checking voltage on a connected running device? Or maybe a DVM is totally useless for this task?

Do you guys have a recommended 'smart' testing device that does a full test of the switch port, checking different protocols, etc?

Note that I did the search and found info and discussions around cable testers, hare/hound tone tracers etc. Not finding a lot about PoE-specific testing.

 

[sebastiantombs]

Amazon.com

Amazon.com

 

[Alaska Country]

Use the same one under a different brand name at the same price point. Works well and saves a lot of time solving a variety of issues. It is not built for heavy duty daily use, but it is also not a $700 device.

 

[rolibr24]

Amazon.com

I can vouch for this kit. I love it. I bought it about two months ago. I love the ability to check cables. Im no pro at making cables, every so often I’ll make one and it doesn’t work. With that tester a simple plug in will tell me that I have a crossed cable. Beats the heck out of Ohm’ing it out with the fluke

 

[sebastiantombs]

I've made literally thousands of cables and I always test them. Heck, I even test the cables that come with any device I buy that has a network cable in it. I've found a lot of bad ones and ones that use "non-standard" wiring schemes.

 

[Teken]

I can vouch for this kit. I love it. I bought it about two months ago. I love the ability to check cables. Im no pro at making cables, every so often I’ll make one and it doesn’t work. With that tester a simple plug in will tell me that I have a crossed cable. Beats the heck out of Ohm’ing it out with the fluke

Just to add some clarity to the statement up above Ohming a line will not tell you a wire / pair is incorrectly inserted into the RJ45 connector. If a person had nothing in the ways of hardware the only method is to eye ball the pairs are inserted and wired correctly. A person would than measure for continuity from end to end to insure there wasn't an open state in the wire and if curious would also measure the resistance in that line.

These cheap wire checkers are indeed a required tool for any DIY - Pro.