web statisticsweb stats Business Phone Systems Tech Talk Forum - VOIP & Cloud Phone Help

Business Phone Systems

Previous Thread
Next Thread
Print Thread
Rate Thread
#265005 11/15/11 05:39 AM
Joined: Aug 2007
Posts: 105
emark Offline OP
Member
OP Offline
Member
Joined: Aug 2007
Posts: 105
I am using 3com POE injectors behind a gigabit switch, the POE injector is a 10/100 device and my phones are 10/100/1000, the phones will NOT link up. When I remove the POE injector from the equation, and use "wall wart" transformers to power the phones, all is good, phones link and talk to my VOIP PBX and the world! Anyone run into this before? Any solution or ideas?

Atcom VoIP Phones
VoIP Demo

Best VoIP Phones Canada


Visit Atcom to get started with your new business VoIP phone system ASAP
Turn up is quick, painless, and can often be done same day.
Let us show you how to do VoIP right, resulting in crystal clear call quality and easy-to-use features that make everyone happy!
Proudly serving Canada from coast to coast.

#265006 11/15/11 06:16 AM
Joined: Feb 2009
Posts: 664
Member
Offline
Member
Joined: Feb 2009
Posts: 664
What phones? What PoE standard (or non-standard) do they support? What is the voltage on the PoE injectors?

For instance, Polycom SIP IP501 use a proprietary pinout so you can't use a 802.3af compliant PoE injector. Have to use their cable or make your own. If I am not mistaken.

The other possible issue, have you tried forcing the port speed on the phones and/or switch?

#265007 11/16/11 06:07 AM
Joined: Aug 2007
Posts: 105
emark Offline OP
Member
OP Offline
Member
Joined: Aug 2007
Posts: 105
Thanks Hawk, I am using Polycom P560 and P670's, they power up just fine via the POE injector, but will not link. I am checking on the POE injector at the ccom site now, and I have the manual on the Polycon phones so will check. I'll let you know the outcome.

#265008 11/20/11 06:28 AM
Joined: Mar 2008
Posts: 54
Member
Offline
Member
Joined: Mar 2008
Posts: 54
Does the phone have the option to force the connection to 100Mb?

#265009 01/28/12 01:48 PM
Joined: Jan 2012
Posts: 28
msa Offline
Member
Offline
Member
Joined: Jan 2012
Posts: 28
Polycom is usually 24VDC, non-standard (i.e. not 802.3af) PoE, on unused pairs.

You can't use a standard PoE injector with those. Even if they come up, they won't link because the data pairs are not isolated enough. (IEEE standard PoE runs the power on the same pairs with data, and capacitively couples the data through to the device.)

Any device that is truly 10/100/1000 should have no problem selecting 10/100 when talking to your PoE injectors. The weak part of auto negotiation is the duplex selection, NOT speed (clock speed is easy to detect.)


Link Copied to Clipboard
Forum Statistics
Forums84
Topics94,262
Posts638,696
Members49,757
Most Online5,661
May 23rd, 2018
Popular Topics(Views)
211,098 Shoretel
187,710 CTX100 install
186,795 1a2 system
Newest Members
BPopilek, Rich F, LewisR, TDKs79, Buttinset
49,757 Registered Users
Top Posters(30 Days)
dexman 18
Toner 11
TDKs79 8
pvj 4
jc2it 4
Who's Online Now
1 members (justbill), 211 guests, and 241 robots.
Key: Admin, Global Mod, Mod
Contact Us | Sponsored by Atcom: One of the best VoIP Phone Canada Suppliers for your business telephone system!| Terms of Service

Sundance Communications is not affiliated with any of the above manufacturers. Sundance Phone System Forums - VOIP & Cloud Phone Help
©Copyright Sundance Communications 1998-2024
Powered by UBB.threads™ PHP Forum Software 7.7.5