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Aspirant

GS108PEv3 PoE Mode A capability ?

Hi, we are contemplating buying some GS108PEv3 switches, or the bigger-port equivalents for our building. We have a number of IP security cameras which are PoE powered. However, many of these are using older Cat5e/6 wiring which is only wired for 2 data pairs, no spare pairs. As a result we would require that the switches support Mode-A PoE, ie. power over the two data pairs, rather than relying on spare pairs. 

 

Can you confirm that these switches will work with 4-wire RJ45 wirings ?

 

Thanks. 

Model: GS108PEv3|ProSafe Gigabit Plus switch with PoE
Message 1 of 10

Accepted Solutions
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NETGEAR Moderator

Re: GS108PEv3 PoE Mode A capability ?

@mcsweeney,

 

I just got a feedback from the higher tier of NETGEAR Support.  The NETGEAR 802.3af/at PoE switches supports ALT-A mode (Ethernet 1,2,3,6 pair) and will deliver power to PD’s (power devices), that should cover 10/100Mbps devices like the the IP camera you have mentioned.  If only using 2 pair cable, the you must make sure that the PD supports ALT-A and must use CAT5 for 10/100M, or CAT5E for 1000M (4pair).

 

If ever your concern has been addressed or resolved, I encourage you to mark the appropriate reply as the “Accepted Solution” so others can be confident in benefiting from the solution. The NETGEAR Community looks forward to hearing from you and being a helpful resource in the future!

 


Regards,

 

DaneA

NETGEAR Community Team

View solution in original post

Message 8 of 10

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NETGEAR Moderator

Re: GS108PEv3 PoE Mode A capability ?

@mcsweeney,

 

Let me inquire this to the higher tier of NETGEAR Support.  I'll post here once I got a feedback.

 

 

Regards,


DaneA

NETGEAR Community Team

Message 2 of 10
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Guru

Re: GS108PEv3 PoE Mode A capability ?

Please not that a connection with just to pairs can only reach a max link rate of Fast Ethernet (100 Mbit/s). With Gigabit Ethernet, there are no spare pairs, all foir pairs (eight strands) are used for communication.

 

We have done some tests in the past with various Netgear PoO and PoE+ switches (like GS510TP, GC110PP, GC510PP, ...) and found e.g. an Arlo Q Plus connected by a patch cable with just the (right) two pairs is powered and an Ethernet link is established to working camera conditions.

 

In my opinion, a standards compliant PoE(+) switch can negotiate power requirements and operate both Mode A and Mode B PDs.

 

Message 3 of 10
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Aspirant

Re: GS108PEv3 PoE Mode A capability ?

Hi, thanks for the reply. I was aware with this configuration I would only get 100MBPS but I think that's ample for our cameras. 

 

I suppose the next question is, is this switch (GS108PEv3) PoE+ (both 803.11at + af compliant), as it is simply described as PoE. 

 

I'd imagine this configuration I am suggesting, though technically compliant with the standard may be rarely enough used to have had its support dropped. 

 

 

Model: GS108PEv3|ProSafe Gigabit Plus switch with PoE
Message 4 of 10
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Guru

Re: GS108PEv3 PoE Mode A capability ?

Any standards compliant 802.3af or 802.3at PSE (endspan [integrated with the PoE switch] or mid-span [PoE injector]) must be able to detect, power and work PDs with alternative A or alternative B versions. The power alternate to be used is defined by 25kOhm resistors on the PD side. 

 

PS. The IEEE standards talk of alternative A and B, not mode A and B.

 

 

Message 5 of 10
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NETGEAR Moderator

Re: GS108PEv3 PoE Mode A capability ?

@mcsweeney,

 

Just a follow-up question, what specific brand and model of device/s that you will connect directly to the GS108PEv3 switch to power it up?

 

 

Regards,


DaneA

NETGEAR Community Team

Message 6 of 10
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Aspirant

Re: GS108PEv3 PoE Mode A capability ?

Message 7 of 10
Highlighted
NETGEAR Moderator

Re: GS108PEv3 PoE Mode A capability ?

@mcsweeney,

 

I just got a feedback from the higher tier of NETGEAR Support.  The NETGEAR 802.3af/at PoE switches supports ALT-A mode (Ethernet 1,2,3,6 pair) and will deliver power to PD’s (power devices), that should cover 10/100Mbps devices like the the IP camera you have mentioned.  If only using 2 pair cable, the you must make sure that the PD supports ALT-A and must use CAT5 for 10/100M, or CAT5E for 1000M (4pair).

 

If ever your concern has been addressed or resolved, I encourage you to mark the appropriate reply as the “Accepted Solution” so others can be confident in benefiting from the solution. The NETGEAR Community looks forward to hearing from you and being a helpful resource in the future!

 


Regards,

 

DaneA

NETGEAR Community Team

View solution in original post

Message 8 of 10
Highlighted
Aspirant

Re: GS108PEv3 PoE Mode A capability ?

Hi, thanks for help. GS108PEv3 was purchased and does indeed work with both Cat5 4-wire Mode-A cabling, and of course Cat6 8-wire Mode-B. 

 

THanks. 

Model: HDX111|Powerline HD Plus Ethernet Adapter
Message 9 of 10
Highlighted
Guru

Re: GS108PEv3 PoE Mode A capability ?

Thank you for the confirmation and the feedback, very useful for future readers!

Message 10 of 10