Is it possible for POE switch to provide power to ports on NON-POE switch?

Jason Shaw
Jason Shaw used Ask the Experts™
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We have an HP 2920-48 port POE switch. We also have 2x HP 2920-48 port NON-POE switches. I was surprised to find today that our new VOIP phones are actually get power when plugged into the NON-POE switch?! Is this possible?? If so, are there possible issues I should consider when configured in this manner. I know we are having issues with the phones losing calls before they can be answered...wondering if related.
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Distinguished Expert 2018

Commented:
That's very odd. The answer to your question should very much be no, unless you have an injector of some sort between the non-POE switch and the phone. Are you sure there isn't some sort of other POE switch in the middle?

Author

Commented:
None. Phone->CAT5>Switch....no adapter or anything in between

Author

Commented:
HP 2920-48G-POE+ Switch (J9729A) and HP 2920-48G Switch (J9728A) - phone is connected to the J9728A
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Distinguished Expert 2018

Commented:
Then I would be concerned.

Author

Commented:
LOL!
Distinguished Expert 2018
Commented:
I just found something very odd. According to this document, all of that line of switches are POE. However, the only ones that highlight that are the POE+ switches. And that would make perfect sense.

http://cc.cnetcontent.com/vcs/hp-ent/inline-content/6H/9/1/9127B67E6007B65EB4421A61875E5D30353FAE26_source.PDF

That's pretty hilarious considering that even HP's own site doesn't acknowledge the ports are POE, yet does mention the POE+ ports on the appropriate models.

Author

Commented:
Wow, I checked online and read they were NOT poe. Strange...but explains why we are getting power
thanks!

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