AF24 Loses Ethernet

[sirhc]

I am actually amazed that you have not blow the Ethernet transformers because the ones in this model are only rated at 0.72A per pair so 1.44 Amps across the 2 pairs.


You said something about getting a lot of Ethernet errors....well that might be why, you may have already damaged the transformers?

[keefe007]

Interesting. This is a brand new AF24 and no surge.

[sirhc]

Interesting. This is a brand new AF24 and no surge.

Something is wrong, 80 watts is not right!

viewtopic.php?f=6&t=537#p3696

[JustJoe]

Hi keefe007, I still go back to thinking about the first AF24 that was / is working... What kind of power numbers were / are you seeing on that port? They should probably not be that much different? Intermittent readings like what you first described on #2 sound like water in the cable / connector.

[sirhc]

Keefe007 used a spare WS-8-250-AC he had and it reports the correct current and as far as I know he is back up and running.

I talked to the engineer and we "think" the Ethernet Transformer was or went bad which was causing the massive power draw. He is sending this unit back to us for exchange and Dave will diagnose the switch when he gets it which might be a couple weeks because Keeke007 will send it to Netonix her in PA but then we will include it in the next shipment to Dave in Toronto Canada so it may be a while to we have what went wrong with that unit but I will post it here once we know but we are pretty sure it is the Ethernet Transformer that is bad.

Keefe007 please make a follow up post to your post over on the UBNT Forums about the out come, maybe cut and paste this reply and/or link back to this post

[Dave]

Keefe007

Any idea if a device was plugged into the port with POE power enabled?

When doing this (plugging in a device with POE power already turned on) there is always a chance that you will get
bad/intermittent connection & to much power might flow through one POE pair instead of both pairs. If this happens
there is always a chance the transformer will go bad to some degree.

Dave

[sirhc]

Keefe007

Any idea if a device was plugged into the port with POE power enabled?

When doing this (plugging in a device with POE power already turned on) there is always a chance that you will get
bad/intermittent connection & to much power might flow through one POE pair instead of both pairs. If this happens
there is always a chance the transformer will go bad to some degree.

Dave

This is why I our policy is to never plug and unplug POE device into live ports on the switch, first turn the POE power OFF.

If you read other manufacturers that make POE switches this is pretty much standard across the board but with our switches we are delivering FAR more current than any POE switch currently on the market at 1.2A rating with the ability upto 1.4A with current models and with the way Poly Fuses work the initial inrush surge on a COLD Poly Fuse before it trips is usually much higher the rated constant load so you could be introducing 2A to the center tap of the Ethernet Surge protector.

This is a more important of a practice of the 48VH configured ports but should be a common practice used when unplugging or plugging ANY live POE on any POE switch.

[keefe007]

No we did not do this! We follow your guidelines of plugging in, then running cable diagnostics, and then turning on power.

[Dave]

Great, thanks for your reply!

[TheHox]

Does this also exist in the 12 port models?
I have a WS-12-250A, and ports 1-4 were all powering 48V devices.
Port 1 AF5xHD 48VH
Port 2 AF24 48VH
Port 3 AF24 48VH
Port 4 AF24 48VH

It's been working fine for a few months, but it seems since its warmer (80s with sun on the cabinet) 2 days ago, all 48V ports stopped working.

We sent a tech out, power cycled the switch, everything came up, so we left.

1 hour later it happened again, the tech went there, power cycled it, opened the door for a couple hours, and everything was fine. He closed the cabinet door that evening.


The next day, ports 3 and 4 AF24s went offline. I was able to login to the switch remotely, I changed the port 1 AF5xHD from 48vh, to 24v, and port bounced ports 3 and 4. They came back for a moment, but again went offline, no LAN, showing some wattage draw but not the normal amount.

On a hunch, I powered down port 4, hoping to at least get port 3 AF24 to operate (it feeds a busier micropop), and that worked. So I sent a tech out and he put the AF24 that was in port 4, into a POE brick for the time. That was yesterday and so far, everything is ok.

So,

Is it too hot?
Is it the same issue as the 8 ports?
48V getting over worked?

WS-12-250A
Firmware Version 1.5.2
Board Rev C