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PoE issues with TL-SG108PE and Unifi Ubiquiti Access Points

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PoE issues with TL-SG108PE and Unifi Ubiquiti Access Points

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PoE issues with TL-SG108PE and Unifi Ubiquiti Access Points
PoE issues with TL-SG108PE and Unifi Ubiquiti Access Points
2022-01-05 14:20:25 - last edited 2022-01-07 07:37:37
Model: TL-SG108PE  
Hardware Version: V2
Firmware Version: Build 20211021 Rel.56865

Hello,

I just got two TL-SG108PE switches but can not get them to provide power.

 

1. I did update to the latest firmware

2. They are integrated in my network and do their switching (with non-poe devices) regularly

 

However, connecting some Ubiquiti Unifi Access Points does not power them.

3. I tried several Access Points, none worked.

4. I connected them on a non-poe-port with an external poe-injector. This works. So the APs are fine.

 

Unfortunately there are no poe-settings in the web interface or the configuration utilities for the SG108PE.

 

Is there any way to turn on or off the poe-function for ports 1-4? Could they be turned off?

What other reasons could there be for the faulty poe function?

 

Thanks in advance!

korky

 

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#1
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2 Accepted Solutions
Re:PoE issues with TL-SG108PE-Solution
2022-01-06 08:27:24 - last edited 2022-01-07 07:34:14

Dear @korky ,

 

korky wrote

@Tedd404 

I tried several cables - among others also one that works in a poe setting with an external injector. So that won't be the problem either.

I don't know about 802.3af. The specs say "passive poe". Could that be the problem? I read somewhere that active poe switches are downward compatible with passive poe devices. Am I wrong?

 

Actually TL-SG108PE support Standard POE not the Passive POE,  @Tedd404  is right, they are not compatible.

This switch cannot supply power to Passive PoE devices.

Please check the specifications of SG108PE as follow:

 

 

Best Regards!

Best Regards! >> Omada EAP Firmware Trial Available Here << >> Get the Latest Omada SDN Controller Releases Here << *Try filtering posts on each forum by Label of [Early Access]*
Recommended Solution
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#7
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Re:PoE issues with TL-SG108PE-Solution
2022-01-06 14:31:32 - last edited 2022-01-07 07:34:24

@korky 

There are two protocols for PoE. Passive and Standard PoE don't work together. Passive usually comes in the form of power adapter. Standard PoE is used most in the business/home camera, AP setup. You can refer to the wikipedia for more knowledge. Some APs are compatible w/ both standard and passive. Some simply support standard PoE.

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
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#8
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7 Reply
Re:PoE issues with TL-SG108PE
2022-01-05 19:30:54

@korky 

No. Switches with 5 or 8 don't support PoE management. Read their user guide and you'll know. Certain models support. 1-4 ports support smart PoE and this only has 55W budget. 

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
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#2
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Re:PoE issues with TL-SG108PE
2022-01-05 20:45:56

@Tedd404 

Thanks for pointing that out. But I am way below budget: all three APs would have a combined 36W, but even with only one connected, it does not work.

 

So any other possible explanations?

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#4
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Re:PoE issues with TL-SG108PE
2022-01-05 23:23:37

@korky 

Cable issue? How long's the cable? For a single unit, what's the PoE requirement? 802.3af? 12w should be okay with this switch. 

Oh. One important thing is that passive poe is not working with this switch. Never know one supports passive poe. Passive uses external power adapter to supply power. 

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
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#5
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Re:PoE issues with TL-SG108PE
2022-01-06 00:59:59

@Tedd404 

 

I tried several cables - among others also one that works in a poe setting with an external injector. So that won't be the problem either.

 

I don't know about 802.3af. The specs say "passive poe". Could that be the problem? I read somewhere that active poe switches are downward compatible with passive poe devices. Am I wrong?

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#6
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Re:PoE issues with TL-SG108PE-Solution
2022-01-06 08:27:24 - last edited 2022-01-07 07:34:14

Dear @korky ,

 

korky wrote

@Tedd404 

I tried several cables - among others also one that works in a poe setting with an external injector. So that won't be the problem either.

I don't know about 802.3af. The specs say "passive poe". Could that be the problem? I read somewhere that active poe switches are downward compatible with passive poe devices. Am I wrong?

 

Actually TL-SG108PE support Standard POE not the Passive POE,  @Tedd404  is right, they are not compatible.

This switch cannot supply power to Passive PoE devices.

Please check the specifications of SG108PE as follow:

 

 

Best Regards!

Best Regards! >> Omada EAP Firmware Trial Available Here << >> Get the Latest Omada SDN Controller Releases Here << *Try filtering posts on each forum by Label of [Early Access]*
Recommended Solution
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  1  
#7
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Re:PoE issues with TL-SG108PE-Solution
2022-01-06 14:31:32 - last edited 2022-01-07 07:34:24

@korky 

There are two protocols for PoE. Passive and Standard PoE don't work together. Passive usually comes in the form of power adapter. Standard PoE is used most in the business/home camera, AP setup. You can refer to the wikipedia for more knowledge. Some APs are compatible w/ both standard and passive. Some simply support standard PoE.

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
Recommended Solution
  1  
  1  
#8
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Re:PoE issues with TL-SG108PE
2022-01-07 07:36:13

@Tedd404 @Hank21 

Thanks for your clarifications. I should have checked that before I bought the switches crying

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#9
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