If the connector is rated for 1.5 amps, they  probably tested it at 3 amps.  
If it was never connected or disconnected under load, I would not have a 
problem in saying 1.5 amps.
I am sure it will be ok at .750 amps.  

From: Bill Prince 
Sent: Tuesday, November 15, 2016 8:31 AM
To: [email protected] 
Subject: Re: [AFMUG] Packetflux & 450M Timing

Like I said before; 375 milliamps per pin/wire.



bp
<part15sbs{at}gmail{dot}com>

On 11/15/2016 7:25 AM, Ken Hohhof wrote:

  I wouldn’t look at the max rating on an RJ45 plug and decide it’s safe to run 
it at that voltage or current level.  The contact is still a couple gold plated 
wires pressing against each other.  Not like your typical connector with much 
higher contact force and area.  And the plug/jack alignment and retention 
method is poor.  And we use them in non ideal situations with cables trying to 
pull the plug one way or the other, vibration from wind or motors, 
condensation, wide temperature swings.

   

  I also recall that currents in this range were used on telephone copper pairs 
to “seal” splices – break down oxidation – and when the current would punch 
through the oxidation, it would causes audible pops.  Now, that was splices not 
modular plugs, I don’t know if something similar happens with an RJ connection.

   

  Gold-gold connections are also susceptible to fretting corrosion, if there is 
even the slightest vibration.  Once that happens, I suspect the connection 
would build up resistance, and running a lot of current through it would cause 
heating and eventually cause failure.  Fretting corrosion can be inhibited with 
a suitable contact lubricant, I don’t know if silicone grease works, I suspect 
not and that you would need both a lubricant and a grease to keep out moisture.

   

   

  From: Af [mailto:[email protected]] On Behalf Of Bill Prince
  Sent: Tuesday, November 15, 2016 9:14 AM
  To: [email protected]
  Subject: Re: [AFMUG] Packetflux & 450M Timing

   

  Way beyond what I would be comfortable with.

   

bp<part15sbs{at}gmail{dot}com> On 11/15/2016 7:10 AM, Chuck McCown wrote:

    300V nominally but you can get 600V cable.  And since those insulation 
ratings are derated, pretty sure you can double them before sparks start 
flying.  

     

    From: Bill Prince 

    Sent: Tuesday, November 15, 2016 7:56 AM

    To: [email protected] 

    Subject: Re: [AFMUG] Packetflux & 450M Timing

     

    What's the breakdown voltage on the insulation for a 22 AWG wire?

bp<part15sbs{at}gmail{dot}com> On 11/15/2016 6:54 AM, Chuck McCown wrote:

      Perhaps jack it up to 1000 volts, 12 amps...

      Run your whole house off of a cat 5.  

       

      Now that would be an interesting youtube video.  

       

      From: Bill Prince 

      Sent: Tuesday, November 15, 2016 7:51 AM

      To: [email protected] 

      Subject: Re: [AFMUG] Packetflux & 450M Timing

       

      Using that kind of power scheme, and 48 volts, you're talking about over 
500 watts? No way!

       

bp<part15sbs{at}gmail{dot}com> On 11/15/2016 6:26 AM, Chuck McCown wrote:

        Tower ground earth ground etc, like Trango does.

         

        Yes, I do, the manufacturer of the jacks I use rates them at 1.5 amps.

        But you better not plug them in under load...

         

        From: Bill Prince 

        Sent: Tuesday, November 15, 2016 7:22 AM

        To: [email protected] 

        Subject: Re: [AFMUG] Packetflux & 450M Timing

         

        All one polarity? Where's the drain? You really think you can get 1-1/2 
amps through each of those teeny little RJ45 connections?

bp<part15sbs{at}gmail{dot}com> On 11/15/2016 6:14 AM, Chuck McCown wrote:

          I am talking about all wires being one polarity.  I think I can get 
12 amps without melting anything.  

           

          From: Bill Prince 

          Sent: Monday, November 14, 2016 5:41 PM

          To: [email protected] 

          Subject: Re: [AFMUG] Packetflux & 450M Timing

           

          Let me be more clear. 

          The circuit that is pins 4,5 (+), and pins 7,8 (-) is one circuit. 
Total of .75 amps.

          The circuit that is pins 1,2 (-), and pins 3,6 (+) is one circuit. 
Total of .75 amps.

          That puts 375 milliamps on each pin and each wire. That's because the 
power/current that is going in on pins 7 & 8, has to return on pins 4 & 5. You 
can't double that.

          Possibly more than I would be comfortable with anyway.

           

bp<part15sbs{at}gmail{dot}com> On 11/14/2016 12:18 PM, Chuck McCown wrote:

            Half an amp per wire on one chart, 3.5 amps on another chart.  
Heating and insulation temperature rating are going to be the limiting factors 
there.  

            Jacks I use have a 1.5 amp rating per pin.  

             

            So, I think you can get 12 amps total if the cable is short enough. 
 

             

            From: Bill Prince 

            Sent: Monday, November 14, 2016 1:11 PM

            To: [email protected] 

            Subject: Re: [AFMUG] Packetflux & 450M Timing

             

            Each pair is one half of a power circuit. So there are 4 halves. 
There are two issues; how much current can each wire carry, and how much 
current can each connector pin can carry. 

bp<part15sbs{at}gmail{dot}com> On 11/14/2016 11:59 AM, Josh Luthman wrote:

              There are four pairs.  AF5x and the H in 24vh or 48vh POE ports 
of Netonix do power over all four pairs.  Speaking with Ubnt support last week, 
AF5x should ideally do four pairs when possible. 

               

              48v (0.75*4a) = 144 watts

               

               

              Josh Luthman
              Office: 937-552-2340
              Direct: 937-552-2343
              1100 Wayne St
              Suite 1337
              Troy, OH 45373

               

              On Mon, Nov 14, 2016 at 2:44 PM, Bill Prince 
<[email protected]> wrote:

                At 48 volts, and .75 amps per pair of power wires, that would 
be 36 watts + 36 watts, or 72 watts total?

                Just noodling here.

                 

bp<part15sbs{at}gmail{dot}com> On 11/14/2016 11:38 AM, George Skorup wrote:

                  For the record, 
http://store.packetflux.com/powerinjector-plus-sync-gigabit-version/ says: 1A 
per port maximum power.  (48 watts at 48 Volts)

                  So.. is the electronic over-current protection the 1A limit? 
Or is this just outdated info? Pretty sure it's >1A because I've "tested" it 
(cable leaking water into the GigE-APC, the port didn't trip, and the card was 
hot as hell).

                  I was also unaware that Cambium won't be supporting 
sync-over-power on the 450m. I imagine the ringing/bounce issue killed that 
idea due to the high power consumption.

                  On 11/14/2016 1:00 PM, Forrest Christian (List Account) wrote:

                    The current products should power the 450M just fine.  The 
rating is 1A per pair per port, so at the 48V you're good up to 96W. 

                     

                    On Nov 14, 2016 7:50 PM, "George Skorup" 
<[email protected]> wrote:

                      The 450m pulls 70 watts. The current 
SyncInjector/PowerInjector+Sync is around 1A max per port. What you could do 
for now is a GigE-POE-APC and the new aux port version SyncBox Junior. 



                      On 11/14/2016 12:34 PM, Matt wrote:

                        Shouldn't the sync over power for the 450M be the same 
as PMP450i?

                        How is the 1u sync injector coming?



                        On Mon, Nov 14, 2016 at 12:30 PM, Forrest Christian 
(List Account)
                        <[email protected]> wrote:

                          All of the currently shipping syncbox product line 
are compatible.  For sync
                          over power, I have the specs, but the design isn't 
done yet.


                          On Nov 14, 2016 5:40 PM, "Sam Lambie" 
<[email protected]> wrote:

                            A question for Forrest mostly. Have you come up 
with a timing product for
                            the 450m AP yet? If not, have you got a timeline 
for release?

                            Sam

                            --
                            --
                            Sam Lambie
                            Taosnet Wireless Tech.
                            575-758-7598 Office
                            www.Taosnet.com

                       

                     

                   

                 

               

             

           

         

       

     

   


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