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  #1  
Old 01-07-2009, 01:35 PM
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Default Polycom Soundpoint IP550/IP650 Review

I thought I would post a minor correction to your otherwise excellent review of these 2 phones.

It is with regards to the power consumption of the phones. You state in your review

"While I was not able to measure the power drawn from each phone, a search online revealed that both phones draw just 6 W. The IP650 draws 12 W with three optional sidecar modules attached. Both draws are within the 802.3af spec of 14.5 W maximum per device, so standard PoE-equipped switches will handle them just fine."

I recently raised a case with Polycom regarding this very issue, and received the following response (after 6 months).

"Polycom phones do support PoE rating according to the 802.3af standard. This requires that the phones supply an electronic signature according to their peak power draw. We are investigating whether per phone model we have sufficient confidence that the peak power draw will not exceed the 6.5W maximum for a Class 2 device such that we could modify the power signature."

and was pointed to the following technical note

http://knowledgebase.polycom.com/kb/...%200%204542134

The issue I experienced was due to the devices not identifying themselves as Class 2 devices ,which caused a problem with the POE switch I was using in an implementation (Zyxel ES-2024PWR).

The issue was that the switch was capable of supporting 24 Class 2 devices (24 x 6.5W =156W) but as the devices did not present themselves as only requiring 6.5W, the switch defaulted to allowing them the maximum available wattage per port (14.5W). As the switch firmware would not re distribute power that wasnt used to other ports this meant that the 24 port POE switch was then only capable of powering 10 phones. We eventually managed to get a unsupported firmware which distributed only power that was required to each port, but this was a lot of hassle.

It could be argued that the switch was at fault but, had the Polycom phones been class 2 compliant this issue would not have occured.

Just thought I would mention this as it may inconvenience others, as it did me.
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  #2  
Old 01-07-2009, 08:53 PM
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We have an identical issue.
Same phones.
Same switch.
Can you give details of how you obtained the firmware.
I would be grateful if you could email me on steve a_t ecutek d_o_t com.
Thanks for any help.

Steve
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  #3  
Old 01-08-2009, 05:12 AM
pjrouse pjrouse is offline
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Quote:
Originally Posted by Unregistered View Post
I thought I would post a minor correction to your otherwise excellent review of these 2 phones.

It is with regards to the power consumption of the phones. You state in your review

"While I was not able to measure the power drawn from each phone, a search online revealed that both phones draw just 6 W. The IP650 draws 12 W with three optional sidecar modules attached. Both draws are within the 802.3af spec of 14.5 W maximum per device, so standard PoE-equipped switches will handle them just fine."

I recently raised a case with Polycom regarding this very issue, and received the following response (after 6 months).

"Polycom phones do support PoE rating according to the 802.3af standard. This requires that the phones supply an electronic signature according to their peak power draw. We are investigating whether per phone model we have sufficient confidence that the peak power draw will not exceed the 6.5W maximum for a Class 2 device such that we could modify the power signature."

and was pointed to the following technical note

http://knowledgebase.polycom.com/kb/...%200%204542134

The issue I experienced was due to the devices not identifying themselves as Class 2 devices ,which caused a problem with the POE switch I was using in an implementation (Zyxel ES-2024PWR).

The issue was that the switch was capable of supporting 24 Class 2 devices (24 x 6.5W =156W) but as the devices did not present themselves as only requiring 6.5W, the switch defaulted to allowing them the maximum available wattage per port (14.5W). As the switch firmware would not re distribute power that wasnt used to other ports this meant that the 24 port POE switch was then only capable of powering 10 phones. We eventually managed to get a unsupported firmware which distributed only power that was required to each port, but this was a lot of hassle.

It could be argued that the switch was at fault but, had the Polycom phones been class 2 compliant this issue would not have occured.

Just thought I would mention this as it may inconvenience others, as it did me.
This post was mine (I forgot to register yesterday).

I would be interested to hear if anyone else has experienced similar problems with other brands of switch?

Thanks

Paul
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  #4  
Old 01-27-2009, 08:24 PM
mgraves mgraves is offline
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As I've not rolled out that many phones in one location this is something that I've not experienced.

We are in process of rolling out 12 phones on a Linksys SRW224G4P.I did all the provisioning remotely but I expect that they don't have all the phone out of the boxes and on desks as yet.

That location has a mix of IP430, IP450 and an IP6000. All on POE.

Michael
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  #5  
Old 01-28-2009, 12:37 PM
pjrouse pjrouse is offline
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Looking at the Cisco website for that model of switch you might be ok if the load sensing works correctly, but it might be worth testing in house if you can?

http://www.cisco.com/en/US/products/...80a36afb.shtml

Quote:
Q. What is the PoE Feature of the SRW224G4P?
A.
Power feeding of Ethernet is limited for fixed 10BASE-T/100BASE-TX ports. The solution can provide maximum output power per PoE port up to 15.4W on 12 ports or 7.5W on 24 ports simultaneously. The Switch provides independent overload and short-circuit protection for each port, LED indicators for power status per PoE port, and supports IEEE802.3af MIB for Power over Ethernet functionality.

For each attached 802.3af-compliant device, the Switch automatically senses the load and dynamically supplies the required power. The Switch delivers power to a device using the two data wire pairs in the twisted-pair cable. Each port can provide up to 15.4W of power at the standard -48 VDC voltage.
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