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The FAQs listed below are for these products:

  • J8164A ProCurve Switch 2626-PWR
  • J8165A ProCurve 2650-PWR
  • J8762A ProCurve Switch 2600-8-PWR with Gigabit Uplink

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Product Information
» Q: What are the ProCurve Power-over-Ethernet (PoE) products and related accessories?
» Q: What is the Maximum Ambient Operating Temperature?

Power Related Questions
» Q: What pairs of wires do the 2600-PWR switches provide PoE power on?
» Q: How much Power-over-Ethernet (PoE) wattage is available for each of the 2600-PWR switches?
» Q: Why didn't you supply enough maximum power for all ports on the 2650-PWR?
» Q: How is PoE power distributed on the 2650-PWR?
» Q: How does the ProCurve 600 RPS/EPS distribute power?

Interoperability
» Q: What PoE devices have been tested and verified to work with the 2600-PWR Series?
» Q: What pre-standard PoE devices are supported on the Switch 2600-8-PWR (J8762A)?
» Q: What PoE devices DON'T work?
» Q: If the 802.3af spec allows for PoE operation on Gigabit, why don't the 2600-PWR switches support this?

Operational Related Questions
» Q: Are there any troubleshooting commands available on the 2600-PWR Series?
» Q: For VOIP implementations, does the 2600-PWR series support priority queuing?

Answers

Q: What are the ProCurve Power-over-Ethernet (PoE) products and related accessories?
J8164A - ProCurve Switch 2626-PWR PoE stackable switch with 24 PoE-ready ports plus
                 2 10/100/1000 ports (Copper or mGBIC option).
J8165A - ProCurve 2650-PWR PoE stackable switch with 48 PoE-ready ports plus 2
                 10/100/1000 ports (Copper or mGBIC option).
J8168A - ProCurve 600 Redundant and External Power Supply (RPS/EPS). Provides switch
                 redundant power and PoE external power for the 2600-PWR Series and PoE power
                 for the 5300xl PoE Module
J8161A - ProCurve Switch xl PoE Module with 24 PoE-ready ports All PoE-ready ports are
                 10/100Base-Tx with HP Auto-MDIX for straight-through or crossover cable support.
J8762A - ProCurve Switch 2600-8-PWR PoE stackable switch with 8 PoE-ready ports plus 1
                 10/100/1000 port (Copper or mGBIC option). With support for Pre-Standard PoE devices.

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Q: What is the Maximum Ambient Operating Temperature?
The 2600-PWR Series are specified with a Maximum Ambient Operating Temperature of 50° C. Proper cooling measures should be taken for the environment where the 2600-PWR switches will be installed. If installed in a closed cabinet, there should be adequate cooling to maintain the switch under the 50° C ambient temperature noting that the 2600-PWR switches generate a fair amount of heat when powering up all ports at maximum power. Other ProCurve products are rated to operate up to ambient temperatures of 55° C.

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Q: What pairs of wires do the 2600-PWR switches provide PoE power on?
PoE power is provided on the Data Pairs (1&2 and 3&6). With ProCurve's Auto-MDIX feature, even though you may use a straight-thru cable for switch-to-switch connections, the PoE power will always be presented to the device on the 1&2 and 3&6 pins. 802.3af compliant Powered Devices accept power over either implementations (data or unused pairs), and furthermore, are designed to be insensitive to the polarity of the DC power. The PoE power will always be presented on the 1&2 and 3&6 pins regardless of using a straight-through or crossover cable.

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Q: How much Power-over-Ethernet (PoE) wattage is available for each of the 2600-PWR switches?
The 2626-PWR and 2650-PWR have internal power supplies that can supply up to 406 Watts of -50V DC for the PoE devices. For the 2626-PWR, that’s enough to supply 15.4 Watts per port for all 24 10/100 ports, the maximum allowed by the 802.3af specification for Power Sourcing Equipment (PSE). For the 2650-PWR, 406 Watts is enough for 24 ports at the maximum allowable wattage, or all 48 ports at an average of 8.4 Watts (the typical wattage requirement for IP Phones).
See “How is PoE power distributed on the 2650-PWR?”
For the 2600-8-PWR, there is 126 Watts, enough for all 8 PoE-ready ports to supply the full 15.4 Watts per port.

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Q: Why didn't you supply enough maximum power for all ports on the 2650-PWR?
In order to supply 15.4 Watts per port for 48 ports, it would have required a power supply that was twice as large and would have been more expensive. It also may have prevented this product from being designed as a 1U switch and would have had to increase the price substantially. Most Power Devices (PD) do not draw Maximum power. A typical IP phone draws 6-8W. There is enough power in the 2650-PWR to power up to 48 phones.

If the connected PoE devices require more power than the internal power supply can fulfill, you can add power with the ProCurve 600 RPS/EPS product (J8168A).

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Q: How is PoE power distributed on the 2650-PWR?
The 2650-PWR uses two separate PoE controllers: one for ports 1-24 and a second for ports 25-48. Each controller requires a minimum of 38 watts of power to operate (and this power is available to be provided to the ports). Power is dynamically allocated to either controller. With its internal 406 Watt 50V power supply, the 2650-PWR has 406-38 = 368 watts available to either controller (since 38 watt is always reserved for the other controller). This means that if you connect PoE devices only to ports 1-24, you would have 368/24 ports = 15.3 watts average per port. If you only connected 2 devices to ports 1 & 2, then the remaining power (368w) would be available to the controller for ports 25-48.

PoE power distribution diagram A

When the 2650-PWR is connected to an external PoE power source, the ProCurve 600 Redundant and External Power Supply (J8168A), the power is split between the two controllers: the internal power supply provides its full 406 watts to the controller for ports 1-24, while the RPS/EPS external unit supplies EPS power for the controller for ports 25-48 (either 408 or 204 watts depending on how many PoE devices are connected to the ProCurve 600). See "How does the ProCurve 600 RPS/EPS distribute power?"

PoE power distribution diagram B

In the case of a power supply failure, the power provided by the ProCurve 600 RPS/EPS unit is then split across the two controllers. In this case, there may no longer be enough power to continue powering up all of the connected devices especially if the ProCurve 600 is connected to two (2) PoE switches (and only delivering 204W of PoE power to each). Lower priority ports on the 2650-PWR will be shut down to allow the higher priority ports to continue to be powered up.

PoE power distribution diagram c

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Q: How does the ProCurve 600 RPS/EPS distribute power?
The ProCurve 600 (J8168A) Redundant and External Power Supply is an optional accessory for the 2600-PWR series and is designed to provide power for two functions: switch operation and PoE operations.

For switch operation power backup, the ProCurve 600 provides -12VDC power on a priority basis to only 1 of its 6 RPS ports. RPS Port #1 is the highest priority, while RPS Port #6 is the lowest. If a device requires -12VDC as a backup or redundant power, only 1 of the devices would be powered up. If a device on a higher priority port were to require -12VDC power, the lower priority port would be shut down.

Supported devices as of October, 2005 for RPS backup are the Switch 2824 (J4903A), Switch 2848 (J4904A) 10/100/1000 stackable products, and the Switch 2626-PWR (J8164A), Switch 2650-PWR (J8165A), and Switch 2600-8-PWR (J8762A) 10/100 Power over Ethernet products.

For PoE operations, the ProCurve 600 provides up to 408 watts of PoE power across its 2 EPS ports. If only 1 PoE switch or module is plugged into the ProCurve 600, then the full 408 watts is available to that single device. If 2 PoE switch or modules are plugged in, then 204 watts is provided to each of the PoE products. There is no mechanism for load sharing of power on the ProCurve 600. Supported devices as of October, 2005 for PoE power are the Switch 2626-PWR (J8164A), Switch 2650-PWR (J8165A), and Switch 2600-8-PWR (J8762A) 10/100 Power over Ethernet stackable products and the Switch xl PoE Module (J8161A - available in 2004) for the 5300xl chassis.

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Q: What PoE devices have been tested and verified to work with the 2600-PWR Series?
Typically, any device that is 802.3af compliant should work with the 2600-PWR Series.
IP PhonesNotes on operation with the 2600-PWR
Mitel 5010, 5020, 5140No issues
Avaya 4600 seriesNo issues
Cisco 7970GNo issues. First of true 802.3af-compliant phones from Cisco. See below for earlier models.
Wireless Access PointsNotes on operation with the 2600-PWR
ProCurve 420 (J8130A & J8131A)No issues
Table last updated: March 1, 2004

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Q: What pre-standard PoE devices are supported on the Switch 2600-8-PWR (J8762A)?
The 2600-8-PWR provides support for the following pre-802.3af standard devices:
  • Cisco 7902G, 7905G, 7912G, 7940G, 7960G IP Phones
  • Cisco Aironet 350, 1100, 1200, 1230AG Access Points
Cisco pre-802.3af standard phones require the use of a straight-through cable from this switch to their device (+DC voltage presented on pairs 1&2, -DC voltage on pairs 3&6). These devices are dependent on the polarity of the DC voltage (a violation of the 802.3af standard) and will not work properly if the Data Pairs (wires 1&2 and 3&6) are crossed over anywhere in the cable plant from a ProCurve Switch 2600-8-PWR switch to the device.

Q: What PoE devices DON'T work?
Not all PoE devices are necessarily 802.3af compliant. Early versions of IP Phones, though they may accept power over the Ethernet cable using their own Mid-Span Power devices, may only accept power over the Non-Data Pairs of wires (Cat5 cable, pins 4&5 and 7&8). The 802.3af specification clearly states that Power Devices MUST accept power over either Data Pairs (1&2 and 3&6) or the Non-Data Pairs. Furthermore, a compliant device must also be 'insensitive' to polarity, meaning that it should power up whether the first pair are +50VDC or -50VDC.

The 2600-PWR switches provide PoE power over the Data Pairs with pair 1&2 being Positive DC.
Generally speaking, devices that cannot or do not claim 802.3af compliancy may not work with our 2600-PWR switches. NOTE: The 2600-8-PWR (J8762A) does support some pre-standard devices. See (What pre-standard devices are supported by the 2600-8-PWR).

Products with known issues
IP Phones Notes on operation with the 2600-PWR
Cisco 7900 series IP Phones Early models of the 7900 series are not 802.3af compliant and only operate under Cisco-proprietary power detection scheme. The 2600-8-PWR (J8762A) can provide power to some of these pre-standard devices. See (What pre-standard devices are supported by the 2600-8-PWR). Only the 7970g is purported to be 802.3af compliant
Siemens OptiPoint 400 version 3.0 According to the datasheet 802.3af compliant. This is an ERROR. The phones only accept power on the Spare Pairs (4&5 and 7&8) and will not power up with 2600-PWR.
The OptiPoint 600 is purported to be 802.3af compliant.
Avaya 1st generation IP phones
4606, 4612 and 4624 Gen 1 phones
Pre-802.3af standard phones. Not powered over Data Pairs. Identified via the Model Code # of the form: 46xx01A-xxx where 'x' is a model specific number, for example, 462401A-003.
2nd Generation phones (Model Code # 46xx02A-xxx) added 802.3af compliancy.
Table last updated: September, 2005

Products with known issues
Access PointsNotes on operation with the 2600-PWR
Cisco Aironet 300 and 1200Pre-standard and only operate under Cisco-proprietary power detection scheme. NOTE: The 2600-8-PWR (J8762A) does support some pre-standard devices. See (What pre-standard devices are supported by the 2600-8-PWR).
Table last updated: March 1, 2004

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Q: If the 802.3af spec allows for PoE operation on Gigabit, why don't the 2600-PWR switches support this?
The focus for the 2600-PWR Series is 10/100 connectivity at the "Edge". The two 1000Base-x ports are focused on inter-switch connectivity, not edge connectivity. At this time (2003), there are probably not that many 802.3af PD's running at gigabit speeds.

See also: "What pairs of wires do the 2600-PWR switches provide PoE power on?" elsewhere in this document.

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Q: Are there any troubleshooting commands available on the 2600-PWR Series?
See the latest Management and Configuration Guide for the 2600-PWR and related switches for the commands pertaining the Power over Ethernet features which can be found on the ProCurve website using the following link: Switch 2600 Series (2626-PWR and 2650-PWR) documentation Commands available on the 2600-PWR switches that would be useful for troubleshooting PoE-related issues would be:

At the Global Level:
show power [interface list]Shows you specifics per port regarding the Power status.
Power Enable      : Yes  
Priority          : Low               Configured Type   :  
Detection  Status : Searching         Power Class       : 0  
Over Current Cnt  : 0                 MPS Absent Cnt    : 0  
Power Denied Cnt  : 0                 Short Cnt         : 0  
Voltage           : 0 dV              Current           : 0 mA  
Power             : 0 mW
At the Interface Level:
NO Power Disables power on the selected ports. You can then provide power to the PoE device out-of-band (i.e. using the native power supply for the device). This would allow you to troubleshoot the device as an Ethernet device without regard to the Power-over-Ethernet function.
Power { Critical | High | Low } Overrides the default priority for providing power to the selected ports. By default, Port 1 has the highest priority.

Q: For VOIP implementations, does the 2600-PWR series support priority queuing?
Yes, the 2600-PWR series supports the 802.1p standard for tagging traffic to four (4) Weighted Round-Robin queues for traffic prioritization.

The Weighted Round-Robin algorithm uses weights of 64, 16, 4, and 1 for the four queues from the highest to the lowest queue. This provides for about 75% of all Hi-priority traffic to be forwarded when a system is fully loaded. Weighted Round-Robin algorithms are useful so that Low-priority traffic queues are not 'starved' when the Hi-priority queue constantly has pending traffic.

Since 802.1p specifies 8 priority levels, implementations with less than 8 forwarding queues (in this case of 4 queues) map the tagged traffic in the following manner:

802.1p priority value used in Tagged VLAN packetsMapped to Outbound QueueRound Robin Weighting
1 (Low)11 (Low)
2 (Low)11 (Low)
0 (Normal or unspecified)24 (Normal)
324 (Normal)
4316 (High)
5316 (High)
6464 (Highest)
7 (High Priority)464 (Highest)
Per-Port prioritization is setup by the following command:
interface [e] <port-list < qos priority > 0 .. 7 >

See the Management and Configuration Guide chapter on "Optimizing Traffic Flow" for more information on setting port priorities and how 802.1p prioritized traffic flows through a 2600-PWR Series switch.

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