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CAT3 POE issue..... yes it does work... but.......

They say it couldnt be done, but yes it does work. I have 4506 switch in my CAT3 closet running POE on 7961 and 7940 phones.

Question I have is, some of my phones will boot up on POE, then about 30 seconds later... flip off and reboot. Does POE have anything to do with the Port setting to 10F or 10H or Auto, etc? Right now, they are set to Auto and I have a couple phones working in some locaitons, others that will not "flip". I suspect it has something to do with the cabling or patch cables, but anything else I should be looking at here?

thanks much!

New Member

Re: CAT3 POE issue..... yes it does work... but.......

I see no reason to think POE would not run on CAT 3. I have allot of Nortel 802.11af compliant phones running on CAT3. One thing I would do is lock the switch ports to 10 full. You do not want them trying to transmit at 100 over CAT3

Re: CAT3 POE issue..... yes it does work... but.......

Actually about 2 hours after i posted this, I decided to try and locking the switch ports to 10 full and then POE started to work how it should. So strange that port speeds affect POE to the phone in a CAT3 enviroment.