.375 amp per wire.  So .750 amp per pair.  
At least that is what I think I finally settled on.  

From: Adam Moffett 
Sent: Tuesday, May 08, 2018 10:53 AM
To: [email protected] 
Subject: Re: [AFMUG] crowdsource troubleshooting

If that's right, would that mean 0.5amp on 4&5 and 0.25amp on 3&6,7&8 ?
Is it a 0.5amp fuse?


------ Original Message ------
From: "Jeremy" <[email protected]>
To: [email protected]
Sent: 5/8/2018 11:42:35 AM
Subject: Re: [AFMUG] crowdsource troubleshooting

  No, that is not true, it adds an additional ground on 3&6.  So to obtain a 
gigabit connection you have + on 4&5 and - on 3&6, 7&8.  All of the present day 
UBNT gear is like this since they added gigabit Ethernet.  When we upgrade we 
add a jumper to 3&6 to get it to negotiate at gigabit, but they seem to operate 
at 100FDX without it.

  On Tue, May 8, 2018 at 9:30 AM, Jacob Turner <[email protected]> wrote:

    The Prism Gen 2 uses "standard" UBNT passive 24v POE.  +4,5 -7,8.  I've 
seen netonix switches claiming as much as 12 watts draw from one when running.  
I wouldn't be surprised if their startup draw may be a bit higher.

    On Tue, May 8, 2018 at 8:16 AM, <[email protected]> wrote:

      I need help in understanding a product failure.

      I have now had two customers with similar failures in my POE fuse 
product.  The fuses are blowing.  
      So far it is limited to the fuses on pins 4/5.

      One customer is using:
      UBNT 5AC Prism Gen 2 radio, Mikrotik 411 boards, using both poes and 
netonix as the power supply.

      What pins and polarities does that radio use for POE?  How much current?

      I may need higher rated fuses or slower fuses.  But I can only go so high 
before it is not protecting Netonix thus becoming an expensive CAT5 splice.  

      My ideas so far:

      I need a slower reacting fuse.

      I need a higher amp rating fuse.  (not sure how high I can go and still 
protect Netonix)

      Some loads have unanticipated currents on those wires.

      Plugging in when powered may cause a connection sequence problem where if 
pin 4 makes contact first the whole load will go through that wire and blow 
that fuse.


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