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Re: UAP-AC-IW no POE for specific cable only

[ Edited ]

@kevindd992002 wrote:

@greggmh123 wrote:

Somewhere in the bowels of my test kits, I have something like this https://www.amazon.com/Greenlee-Communications-1902-Modular-Adapter/dp/B000099O64 to allow testing volctage any way I need to see it.

 

I put that PoE Texas tester into my Amazon cart just for the heck of it.

Gregg


Sorry, but what does that modular adapter exactly do again?


The adapter lets one connect a cable to it and test voltages across whatever wires one wants to test. If desired, connecting the other end so it's inline exposes the eight wires for testing a live circuit without having to poke a wire's insulation. In the auto industry, we had a version of it that was called a "breakout box" because it would sit inline and "break out" the wiring for probing voltages without damaging the wiring (similar to this thing https://www.amazon.ca/OTC-Ford-EEC-V-104-Breakout/dp/B000IPRW26).

 

I was thinking more of passive PoE when I mentioned the adapter. So, you could put this inline at the AP end with the D-Link cable in one side and a short patch cable in the other side going to the AP. Connect the D-Link cable side only, test voltage on the Mode A pairs (which may not be powered there due to no PD on the line, then connect the AP to the other side and see if the voltage drops or stays good. If the voltage drops, but it works on the AP side of the coupler, you have bad D-Link termination or cable.

 

I should have my PoE Texas tester tomorrow and will let you know how well it works.

Gregg

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Re: UAP-AC-IW no POE for specific cable only

[ Edited ]

The PoE Texas "PoE Tester GEN2" device arrived today and it does not seem to work the way the manual indicates. Per step 1 in the manual, if I connect a cable from my Cisco SG300-10PP 802.3af/at switch to the Power In port, and connect the Power Out port to my UniFi UAP-AC-IW 802.3af/at access point, with the Simulate PoE Device switch OFF, it should be in PoE pass-through mode, and the AP should power up and the tester should show information. However, nothing happens.

 

The tester's display stays off, and the access point does not power up. However, if I slide the Simulate PoE Device switch to On, then the display lights up and the access point comes online. I also tested my Cloud Key Gen1 as above but got the same results.

I just emailed their tech support and should hear back from them on Thursday.


EDIT: Their response was "Since your PSE is active, or auto-negotiating, the 'simulate POE device' option has to be turned 'ON' for this negotiation to take place. Once the negotiation happens, the switch can then be turned off and 'Passive PoE' will appear on the screen." That is not what the manual states, and it goes against what PoE "pass-through" means, at least to me (to me, it should pass both negotiation and power; don't make the tester do the noegotiation). I returned the tester today.

 

Gregg

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Re: UAP-AC-IW no POE for specific cable only


@greggmh123 wrote:

The PoE Texas "PoE Tester GEN2" device arrived today and it does not seem to work the way the manual indicates. Per step 1 in the manual, if I connect a cable from my Cisco SG300-10PP 802.3af/at switch to the Power In port, and connect the Power Out port to my UniFi UAP-AC-IW 802.3af/at access point, with the Simulate PoE Device switch OFF, it should be in PoE pass-through mode, and the AP should power up and the tester should show information. However, nothing happens.

 

The tester's display stays off, and the access point does not power up. However, if I slide the Simulate PoE Device switch to On, then the display lights up and the access point comes online. I also tested my Cloud Key Gen1 as above but got the same results.

I just emailed their tech support and should hear back from them on Thursday.


EDIT: Their response was "Since your PSE is active, or auto-negotiating, the 'simulate POE device' option has to be turned 'ON' for this negotiation to take place. Once the negotiation happens, the switch can then be turned off and 'Passive PoE' will appear on the screen." That is not what the manual states, and it goes against what PoE "pass-through" means, at least to me (to me, it should pass both negotiation and power; don't make the tester do the noegotiation). I returned the tester today.

 

Gregg


Thanks for reporting back. So I take it you don't recommend that tester anymore? Did you reply back to their email and argue what the "standard" is?

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Re: UAP-AC-IW no POE for specific cable only

I never recommended that tester in the first place. I said, "Supposedly, this tester...", wondering if it would live up to its advertising. For me, it did not do so, so I returned it. The detector part of it did work properly, detecting a 24V passive PoE injector and 802.3af/at switch, but the tester portion with the display did not work as they stated.

 

Yes, I did email them and they said they would pass along my comments to engineering. I still have my Fluke LRAT-2000 kit and the LinkSprinter 300 that was a free add-in, so I am not lacking for tools; I was just curious about theirs.


Gregg

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Re: UAP-AC-IW no POE for specific cable only

You never mentioned that you tried another PoE port on your switch, with the AP in the position 63 meters away. Just to be sure, you did that, right? So we can rule out a port issue. It's not because it works with a short cable that a port issue is to be ruled out..

 

Also, what kind of switch are we talking here? If it's a US8P150, and the cable is in port 3/4 or 7/8, then try ports 1/2 or 5/6 instead.

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Re: UAP-AC-IW no POE for specific cable only


@greggmh123 wrote:

I never recommended that tester in the first place. I said, "Supposedly, this tester...", wondering if it would live up to its advertising. For me, it did not do so, so I returned it. The detector part of it did work properly, detecting a 24V passive PoE injector and 802.3af/at switch, but the tester portion with the display did not work as they stated.

 

Yes, I did email them and they said they would pass along my comments to engineering. I still have my Fluke LRAT-2000 kit and the LinkSprinter 300 that was a free add-in, so I am not lacking for tools; I was just curious about theirs.


Gregg


Ok, thanks.

 


@asclepi wrote:

You never mentioned that you tried another PoE port on your switch, with the AP in the position 63 meters away. Just to be sure, you did that, right? So we can rule out a port issue. It's not because it works with a short cable that a port issue is to be ruled out..

 

Also, what kind of switch are we talking here? If it's a US8P150, and the cable is in port 3/4 or 7/8, then try ports 1/2 or 5/6 instead.


Sorry, I forgot to mention that but yes I did that. That's the very first thing I did. It's definitely not a port issue. The port where this AP is originally plugged in works with other PoE devices too.

 

We're talking about a USW-16-150W switch here. It's not a port issue.

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Re: UAP-AC-IW no POE for specific cable only

Is the affected AP the one that happens to be the farthest away from the switch?

 

How many other devices draw power?

 

Is the switch temperature in the normal range?

 

Can you find anything relevant in the logs: https://help.ubnt.com/hc/en-us/articles/204959834-UniFi-How-to-View-Log-Files

 

Did you consult:

https://community.ubnt.com/t5/UniFi-Routing-Switching/USW-16-POW-150W-dropping-POE-but-not-overheati...

https://community.ubnt.com/t5/UniFi-Routing-Switching/UniFi-Switch-16-POE-150W-Overheat/td-p/2227548

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Re: UAP-AC-IW no POE for specific cable only


@asclepi wrote:

Is the affected AP the one that happens to be the farthest away from the switch?

 

How many other devices draw power?

 

Is the switch temperature in the normal range?

 

Can you find anything relevant in the logs: https://help.ubnt.com/hc/en-us/articles/204959834-UniFi-How-to-View-Log-Files

 

Did you consult:

https://community.ubnt.com/t5/UniFi-Routing-Switching/USW-16-POW-150W-dropping-POE-but-not-overheati...

https://community.ubnt.com/t5/UniFi-Routing-Switching/UniFi-Switch-16-POE-150W-Overheat/td-p/2227548


I cannot confirm if it's the farthest one away from the switch based on cable length. I got the 63 meters value from the test results of the Intel NIC in a laptop. I have CCTV cameras all around the house which may or may not be longer than 63 meters.

 

I have two switches. On the switch where this AP is connected, I have a total of 4 UniFi AP's and 1 Netgear PoE switch connected to it.

 

The switch temp is 70C. I know that's high for you guys in the US but that's normal for devices here in the Philippines. And it's very far from reaching any temp limits anyway. There's a long-standing issue for these 16port switches now wherein their fans never turn on even if it reaches high temps. It's a bummer but Ubiquiti wouldn't even acknowledge that it's a problem. Regardless, I doubt this is the issue.

 

I haven't checked the logs but what am I looking for? I mean, if another PoE device works on the same port and I know that uses a longer than usual CAT6 cable as well, wouldn't that already tell us that the issue is the cable itself?

 

I'm part of both those threads for a long time now. But like I said, I don't think it's the same issue. The issue explained there (which I already experienced a few times, so I'm familiar with it) is that PoE is fluctuating and reboots the AP's randomly. My issue in this thread is that this particular AP does not turn on at all.

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Re: UAP-AC-IW no POE for specific cable only

In any case, here's the logs of the switch in question:

 

https://hastebin.com/ipubedahol.sql

 

The affected AP is connecting at port 11 and as expected I don't see any logs for it there.

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Re: UAP-AC-IW no POE for specific cable only

"My issue in this thread is that this particular AP does not turn on at all."

My recommendation is to get a tester that can show you the voltage and current available or in use. I think that the PoE Texas tool can do the inline PoE voltage/wattage tests for what you need if you turn on its "Simulate PoE Device" button. I just didn't like it for how it works, e.g., not how the manual implies, but it WILL show the PoE voltage and current.

Gregg

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Re: UAP-AC-IW no POE for specific cable only

Ok, as I said I'm on site today (until tomorrow) and did a couple of tests more. I think I isolated the issue to what's more a likely cause for me than a defective cable. My doubt was high that the cable was the one at fault from the beginning anyway. Here's what I did (in the same order):

 

1. Tested the setup as is with my ne Klein Tools VDV Scout Pro 2 tester to see if there are any miswires, split wires, open, or short. And there were none.

2. I wasn't new to RJ45 CAT6 cable termination so I was confident that the termination I did on this is ok. But nobody's perfect so for the heck of it I re-terminated the remote end of the cable where the AP is directly connected.

3. After doing step 2, for some unknown reason the AP went up and got PoE from the switch successfully!!! So I thought everything was wokring fine already and decided to just post my findings here and be done with the issue. But after 2 or 3 hours, the AP suddenly went down again Man Sad

4. I repeated step 1 and everything was passing.

5. From two weeks ago, I told you guys that this AP was plugged into port 11 and that I already tried plugging it to another port of the "same" switch (let's call it siwtch1) to no avail. I also tried plugging another AP to port 11 and everything was working properly. So that made me conclude that the port wasn't the problem. What I did not try (because I forgot was to plug the AP into another PoE switch (let's call it switch2)! I have two USW-16-150W switches. So I did that and the AP went up!!!

 

So from these observations, my new conclusion is that switch1 is somehow blocking this particular AP from getting PoE from it (any port that I plug it into). But for some reason switch 2 accepts the AP willingly.

 

Are there any logs in switch1 that I can check to see what's going on? Any other troubleshooting ideas that you think I need to do while I'm on site?

 

Thanks a bunch!

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Re: UAP-AC-IW no POE for specific cable only

Connect the cable in the bad port and continue to put some pressure on the connector, like you are pushing it in. Give it some time to complete PoE negotiation. If it helps, it's a bad contact between the connector and the port. If it doesn't, repeat with pulling the connector up from below, and then again with pushing the connector down from above. Try at both ends.

 

Give time for PoE negotiation, watch the controller and see if it is drawing power.

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Re: UAP-AC-IW no POE for specific cable only

I can do that. But how do you explain the cable working on another PoE switch? As soon as I plug it in switch2, I see the left orange light (PoE light) go on after 2 seconds, same cable and all.

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Re: UAP-AC-IW no POE for specific cable only

Port issue where contact is not entirely made, resulting in all kinds of undefined behavior that differs depending on the characteristics of the cable that is plugged in.

 

https://community.ubnt.com/t5/UniFi-Routing-Switching/US-8-150W-Port-8-wont-pass-data-with-PoE-on/m-...

 

Note that the log messages were different. Your logs point more towards the 16P switch PoE specific issues, but this is something you can rule out while on site

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Re: UAP-AC-IW no POE for specific cable only

I attemped to perform your tests but as soon as I plugged the cable back in the affected port, it went up. I then tried pushing it all the way in, pulling it back slightly, pushing it from below/above, and there was no effect. If this was bad contact like what you're saying, these should've been observed:

 

1. Plugging in another of my patch cables (from my patch panel going to other AP's) should experience the same symptoms.

2. Performing your tests would've disconnected my AP again (no left orange light) immediately.

 

I still don't think it's a bad port but please enlighten me if I'm missing any of the points you're trying to suggest here. I'm really curious as to what's causing this abnormal behavior.

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Re: UAP-AC-IW no POE for specific cable only

If you did this at both ends, I agree that a bad contact is most likely to be ruled out. As you said, the AP would have disconnected.

 

However, I did this test with the AP being disconnected - while everything is plugged in - and seeing it come online with just a little pressure on the connector.

 

Note that It's not necessarily the case that another cable would show the same symptoms. In my situation, I had cables that did show symptoms, while others did not, depending on the characteristics of the cable. This also doesn't apply if the problem is actually the connection at the AP's end or some kind of interference along the run of the cable.

 

Seeing that the log and model match with what is described in the 16P PoE issue topics, I'm gravitating towards that as the explanation.

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Re: UAP-AC-IW no POE for specific cable only


@asclepi wrote:

If you did this at both ends, I agree that a bad contact is most likely to be ruled out. As you said, the AP would have disconnected.

 

However, I did this test with the AP being disconnected - while everything is plugged in - and seeing it come online with just a little pressure on the connector.

 

Note that It's not necessarily the case that another cable would show the same symptoms. In my situation, I had cables that did show symptoms, while others did not, depending on the characteristics of the cable. This also doesn't apply if the problem is actually the connection at the AP's end or some kind of interference along the run of the cable.

 

Seeing that the log and model match with what is described in the 16P PoE issue topics, I'm gravitating towards that as the explanation.


Yeah, mine wasn't a case of bad contact because the cable worked fine with another switch and another cable worked fine on the affected port. Now, it has been working for several days without any issues. I don't know what caused the issue but it is what it is. I'll report back when I encounter the same issue. Thanks for the help.

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