3560 is not powering phones until you us a poe tester to turn on the power

Unanswered Question
Mar 26th, 2009
User Badges:

I'm in the middle of installing a new Shoretel phone system and I'm trying to power the phones with 3560 switches. In several of my locations, when I plug in a Poe device, Shoretel phone or linksys switch, I receive no power from the switch. I have a Poe tester that I use to test the port and that comes on immediately when I plug it into the network drop. After I plug in the tester I can then plug in the phone or other Poe device and it works correctly. I'm pretty sure it has to do with older cabling int the walls because new drops do not have this problem or if I plug the Poe device into the switch with just a patch cable it comes on like it is supposed to. My question is this, can I use the power inline static command on the ports I want to be enabled for phones to make sure power is always on? Also, can I use the power inline consumption command in conjunction with the static command to make that port only provide 7.0 instead of the full amount? We have 48 port switches so it is not possible to provide full power to all ports like the static command tries to do.


Thanks!

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Mohamad Qayoom Thu, 03/26/2009 - 10:04
User Badges:
  • Bronze, 100 points or more

The only concern I have here is what will happen you you accidentally plug in a non poe device and have the "power inline static command configured on the port." This can potentially damage the non-poe device.

andrew.butterworth Thu, 03/26/2009 - 10:43
User Badges:
  • Gold, 750 points or more

The 'power inline static' command does not permanently apply power to a PoE port, it just reserves power for it. The PoE device must still be detected as a PoE device before the port will supply power.


http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_50_se/command/reference/cli1.html#wp10762288


It is obviously an issue with your cabling as you say connecting a device directly to the switch with a patch cable works. I suggest you investigate the cabling and ensure it is wired correctly and isn't overlength.


HTH


Andy

bailessm Thu, 03/26/2009 - 10:47
User Badges:

Thanks for the info, I didn't realize that the static command didn't turn the power on and leave it on. The cable is wired correctly and it is not overlength but it is older cat5 cable not 5e or cat6. I'm hoping to find something that will save me from haveing to recable most of our older branches.

Actions

This Discussion