Stop making sense... it's disturbs the space time continuum
On Jan 4, 2016 5:33 PM, "That One Guy /sarcasm" <[email protected]>
wrote:

> POE is quite the crackwhore of terms nowadays, alot of people use her in
> alot of different ways and nobody wants to pay much. I wish there was just
> a design standard that just auto sensed and applied, 24v 48v pick a pair.
> Just to eliminate the additional stocking of appropriate power supplies and
> surge suppression, they would be worth a little more, and if it were to
> become common the cost would drop
>
> On Mon, Jan 4, 2016 at 5:30 PM, George Skorup <[email protected]> wrote:
>
>> I believe Phihong wired it that way so that you can use it as a 3at
>> compliant injector where only two pairs may be present (so 10/100 only). IP
>> phones come to mind. We run into a lot of older-ish structured wiring where
>> they ran only one cat5 and stole one pair for phone and two pairs for
>> ethernet. Not the way I'd do it, but whatever. Most of the phones we're
>> using now have a built-in GigE switch.
>>
>> I remember seeing in the 450i guide that it will take either polarity on
>> all pairs. If you're not using the aux port, then two pairs for power (30W)
>> will be fine. If you are, or I suppose if it's a long run, then all four
>> pairs for power would be warranted. I really like this PoE design. Would be
>> nice if the regular 450 APs would take 48-56VDC. I know they talked about
>> that at one point, but it looks like we're limited to 30VDC. Well, at least
>> that's what the label says.
>>
>> The whole pin swapping thing with the 450i and CMM4 is because 56VDC mode
>> on the CMM4 is wired for the split pair 320/430 config. With the AP being
>> pair polarity agnostic, you don't need to do the swapping when using a
>> SyncInjector. Basically it will take the standard Canopy POE pinout, just
>> needs to be >=48VDC. Probably more like >40VDC.
>>
>> On 1/4/2016 12:50 PM, Ken Hohhof wrote:
>>
>> Good point about the power being on 1/2 and 3/6.  I guess that makes it
>> 802.3at Alternative A wiring.  According to the schematic, 4/5 and 7/8 are
>> wired straight through with no transformer.  So gigabit compatible with
>> only 2 transformers.  Probably for non gigabit compatible, Alternative B is
>> cheaper because you don’t need any transformers at all.  And the 60-75 watt
>> POEs use all 8 wires for data and power, so 4 transformers.
>>
>> So confusing!
>>
>> I can’t find any wiring diagrams for the Cambium N000065L001B, but at 60
>> watts, I guess it must use all 8 wires for power.  Hence the price?
>>
>> Something else I notice is the Cambium POE is rated for 0 to 40C, while
>> the Phihong unit is rated –20 to +65C.  Cambium tells you to use a PIDU for
>> non controlled environment.  Or Netonix or GIGE-POE-APC or Syncinjector.
>>
>> Still, AC powered POEs are handy for configuring radios on the bench, or
>> like that case where I needed a POE at a customer’s office to power a SIP
>> paging amplifier.
>>
>>
>> *From:* George Skorup <[email protected]>
>> *Sent:* Monday, January 04, 2016 2:35 AM
>> *To:* [email protected]
>> *Subject:* Re: [AFMUG] 802.3at POEs
>>
>> It's cheaper at Allied:
>> http://www.alliedelec.com/phihong-poe36u-1at-r/70124112/
>>
>> Yeah, if you're not going to use the Aux port on the 450i, there's no
>> reason to buy a 60W injector. Just keep in mind that this Phihong injector
>> is power over the 10/100 data lines. And is - on 1&2, + on 3&6. It'll work
>> perfectly fine with the 450i APs and 5GHz SMs. And obviously the Exalt
>> ExtendAir G2. The 450i is awesome with the any pair power setup.
>>
>> The one thing I will say about this thing is that it runs a bit hot and
>> if your hearing is decent, you can definitely hear the switcher whining
>> away.
>>
>> On 1/3/2016 7:29 PM, Ken Hohhof wrote:
>>
>> I'm getting more and more equipment with 802.3at POEs, and I feel like
>> I'm getting raped on the price if I get the POE from the equipment vendor.
>> High price and minimal features.
>>
>> My Exalt G2 radios came with these really nice POEs that have diagnostic
>> LEDs and tabs for wall mounting as well as rubber feet for desktop use.
>> The only downside is they are kind of big, but that's not necessarily bad,
>> that may help prevent overheating.  It has LED indications for valid
>> 802.3af and 802.3at signatures, as well as a flashing overload indication.
>>
>> I looked up the part number, expecting them to be expensive, but Digi-Key
>> has a bunch of them in stock and the price is quite reasonable ($38 in
>> single quantity).
>>
>> <http://www.digikey.com/product-detail/en/POE36U-1AT/993-1088-ND/2384576>
>> http://www.digikey.com/product-detail/en/POE36U-1AT/993-1088-ND/2384576
>>
>> From the picture, this is also the POE that I should have gotten from
>> CyberData to go with the SIP paging amplifier I bought, but instead they
>> sent a cheaper L-Com POE that has just one dumb LED to show it is getting
>> AC power.  So I paid something like $64 for a $31 POE.
>>
>> The $100 Cambium POE for 450i is probably more than 36 watts in case you
>> want to use the AUX port on the AP, but it lacks the nice mounting tabs and
>> diagnostic LEDs.  And 36 watts should be more than enough to power just the
>> AP.
>>
>> So I’m inclined to just buy a bunch of the nice Phihong units and use
>> them on everything.  Am I missing something?
>>
>>
>>
>>
>
>
> --
> If you only see yourself as part of the team but you don't see your team
> as part of yourself you have already failed as part of the team.
>

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