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hairfarmer
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wAP AC units over POE don't get enough power.

Wed Mar 01, 2023 9:50 pm

Has anyone else had POE issues with wAP AC units lately?

I have 6 units that will fail to power on fully unless I turn off the 5GHz radio.

The cabling is CAT 5e and if there is a short run it works well, if its 100ft of cable this will not get enough power to run.

I have swapped out APs and power injectors and power supplies and it continues to be a problem however I have had these wAP AC units running since pre pandemic and they were fine.

The config is run from CAPsMAN so I just turn off the 5GHz config and then they run on 2.4GHz.
 
liviu2004
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Re: wAP AC units over POE don't get enough power.

Wed Mar 01, 2023 10:02 pm

No issues, what voltage do you use to power this up and what is the loaded voltage at the unit?
 
hairfarmer
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Re: wAP AC units over POE don't get enough power.

Wed Mar 01, 2023 11:44 pm

No issues, what voltage do you use to power this up and what is the loaded voltage at the unit?
Measured voltage at 23.2VDC at one problematic unit.
 
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mkx
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Re: wAP AC units over POE don't get enough power.

Wed Mar 01, 2023 11:49 pm

No issues, what voltage do you use to power this up and what is the loaded voltage at the unit?
Measured voltage at 23.2VDC at one problematic unit.
Voltage is fine if it was measured while wAP ac was drawing power (wAP ac can take as low as 11V). If the measurement was done when wAP ac was off, then the measurement is inconclusive (or even shows problem ... PAs when idle tend to output voltages slightly higher than their nominal voltage).

Did you try with new power adapters? When PAs age, some capacitors may dry out (or bulge, those can be quite easily spotted)) and whole PA starts to malfunction in weird ways, e.g. the output power is not filtered, can contain dips in voltage which in turn can upset powered device. Also devices (wAP ac) have built-in DC-DC downconverters and those can also age (and malfunction). So how old are those failing units?
 
hairfarmer
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Re: wAP AC units over POE don't get enough power.

Tue Mar 07, 2023 10:38 pm


Did you try with new power adapters? When PAs age, some capacitors may dry out (or bulge, those can be quite easily spotted)) and whole PA starts to malfunction in weird ways, e.g. the output power is not filtered, can contain dips in voltage which in turn can upset powered device. Also devices (wAP ac) have built-in DC-DC downconverters and those can also age (and malfunction). So how old are those failing units?
The age is around 5-6 years old now. I have a bunch of spare or swappable devices and multiple power supplies also don't work (with the only qualification that they don't work over the same cable pulled around 2003).

Having said that, the equipment is approximately the same age, just different, so I haven't put in brand new equipment to test.

My next test will be to use a POE switch and ditch the injectors, see if that makes a difference. Man, have been waiting years for a Mikrotik POE switch - but ultimately may go for a used Cisco unit.

Thanks for the informative reply, my dude.
 
ncd
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Re: wAP AC units over POE don't get enough power.

Sun Oct 22, 2023 5:58 pm

apologies for resurrecting an old thread from 6mo+ ago but did you ever get to the bottom of this?

I've recently had a couple of units seemingly go bad too - I thought it was the power supplies so swapped those out for new known good ones, then I thought the cable run was at fault so provided power right at the site but to no avail. I swapped the units out with spares and then populated with backed up config and the new ones were fine.

I have the old ones on my bench, kind of looking at me. It seems similar but opposite to what you had.

The 5Ghz radio is just fine, I can sustain 100Mbit + in both directions with iperf to a host on the network but as soon as I use the 2.4GHz radio I'm getting kilobytes!

Anyone seen similar?

I've seen some posts on wifi perf suggesting antenna gain etc, I've compared these between old and new and it's identical just one works well and one sucks!

Open to any ideas to save these becoming e-waste.

Thanks,
N

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