Sounds like a cool device.  Excited to see the finished project.

On Mon, Mar 21, 2016 at 9:04 PM, Chuck McCown <[email protected]> wrote:

> It is the mixed rail that seems to be the interesting part.  I have been
> asked multiple times.
>
> *From:* George Skorup <[email protected]>
> *Sent:* Monday, March 21, 2016 8:50 PM
> *To:* [email protected]
> *Subject:* Re: [AFMUG] Fuse question
>
> In all honesty, we won't ever use it. Remote power control per
> device/radio via one PacketFlux device or another is what we do everywhere.
>
> I'm sure someone will use it, so don't take my narrow-minded opinion to
> heart.
>
> I do have one question about the APC cards. Would it be possible to flip
> the RJ45s around so that the tab faces away from the board? That is
> probably the only complaint I have with them.
>
> On 3/21/2016 9:36 PM, Chuck McCown wrote:
>
> Yes, it is an alternate form factor.
> May as well spill the beans.
>
> Something Gino asked for a couple of years ago but never found the
> solution until recently.
>
> I have a 24 position rack mount, same size as the 4 position DIN I sell
> now.
> I am putting a power back plane in it.  It will have 4 separate isolated
> power buses.
>
> Couldn’t find the power bus connectors I wanted until lately.
> Actually they were available but only in bulk.   They recently packaged
> them so my pick n place machine could put them on the board.
>
> So you can mix 4 different POE voltages in each rack.  A/B powering.
> Two common point powering connectors in the back.  Diode combiner.
> You only need one if  you only have one source of power.
>
> Mix –48 and +48 and 24 and 12 all in the same rack.
> No wires going to each individual GIGE-POE-APC.
>
> The surge suppressor will be the GIGE-POE-PRM
>
> *From:* Jeremy <[email protected]>
> *Sent:* Monday, March 21, 2016 7:07 PM
> *To:* [email protected]
> *Subject:* Re: [AFMUG] Fuse question
>
> I am perfectly happy with the GIGE-POE-APC the way it is now.  I haven't
> lost one in three years.  Is this finding a solution to a problem that
> doesn't exist?
>
> On Mon, Mar 21, 2016 at 7:01 PM, Chuck McCown < <[email protected]>
> [email protected]> wrote:
>
>> It is also a POE inserter.
>>
>> *From:* George Skorup <[email protected]>
>> *Sent:* Monday, March 21, 2016 4:40 PM
>> *To:* <[email protected]>[email protected]
>> *Subject:* Re: [AFMUG] Fuse question
>>
>> Let a surge suppressor be a surge suppressor. I will handle the
>> over-current externally (fuses, PacketFlux electronic, etc).
>>
>> On 3/21/2016 3:37 PM, Chuck McCown wrote:
>>
>> Yeah, I am coming to that conclusion I think.
>>
>> *From:* Forrest Christian (List Account) <[email protected]>
>> *Sent:* Monday, March 21, 2016 2:32 PM
>> *To:* af <[email protected]>
>> *Subject:* Re: [AFMUG] Fuse question
>>
>>
>> You need to look at the curve on the polyfuse.  Because the trip is
>> related to heating which is related to current it will trip much faster in
>> many circumstances. ...  however the trip current varies widely with
>> ambient temperature as well.
>>
>> I'm not convinced that you can actually find a polyfuse which will
>> protect Ethernet magnetics.
>> On Mar 21, 2016 4:14 PM, "Chuck McCown" < <[email protected]>
>> [email protected]> wrote:
>>
>>> The poe card would not be the cause, it would be the victim.  The AP or
>>> wiring would be the cause.
>>>
>>> The polyfuse I am looking at takes 12 seconds to blow.  Trying to
>>> protect the power supply and other loads in parallel.
>>> Not sure if that is fast enough to be of great value.
>>>
>>> If one AP shorts out, you don’t want it taking down others that are off
>>> the same power supply.
>>>
>>> *From:* Josh Luthman <[email protected]>
>>> *Sent:* Monday, March 21, 2016 2:07 PM
>>> *To:* <[email protected]>[email protected]
>>> *Subject:* Re: [AFMUG] Fuse question
>>>
>>>
>>> Meh just replace the card if it's being troublesome.
>>>
>>> Josh Luthman
>>> Office: 937-552-2340
>>> Direct: 937-552-2343
>>> 1100 Wayne St
>>> Suite 1337
>>> Troy, OH 45373
>>> On Mar 21, 2016 4:05 PM, "Chuck McCown" < <[email protected]>
>>> [email protected]> wrote:
>>>
>>>> Well, they have their downside.
>>>> A real fuse will be easier to notice when it is blown.
>>>> A poly fuse just cuts the current way down.
>>>> More of a troubleshooting issue than anything else.
>>>>
>>>> But, if a fuse is blown,  then you have to fix the circuit and find a
>>>> replacement fuse.
>>>> I do have LEDs and by unplugging the short circuit cable the LED should
>>>> come back to full brightness.
>>>>
>>>> Just thinking out loud here.  Want to make the right choice.
>>>>
>>>> *From:* Josh Luthman <[email protected]>
>>>> *Sent:* Monday, March 21, 2016 2:02 PM
>>>> *To:* <[email protected]>[email protected]
>>>> *Subject:* Re: [AFMUG] Fuse question
>>>>
>>>> Cheaper to run a polyfuse...why bother asking???
>>>>
>>>>
>>>> Josh Luthman
>>>> Office: 937-552-2340
>>>> Direct: 937-552-2343
>>>> 1100 Wayne St
>>>> Suite 1337
>>>> Troy, OH 45373
>>>>
>>>> On Mon, Mar 21, 2016 at 4:01 PM, Chuck McCown < <[email protected]>
>>>> [email protected]> wrote:
>>>>
>>>>> Still leaning toward the polyfuse.  Not a lot of room, fuses and fuse
>>>>> holders are more money.
>>>>>
>>>>> *From:* Bill Prince <[email protected]>
>>>>> *Sent:* Monday, March 21, 2016 1:51 PM
>>>>> *To:* <[email protected]>[email protected]
>>>>> *Subject:* Re: [AFMUG] Fuse question
>>>>>
>>>>> Most of ours are now the DIN-mounted double feed that uses the 5x20mm
>>>>> glass fuses. However, we also have a few legacy sites that use the
>>>>> automotive blade fuses.
>>>>>
>>>>> If something new came along, we would use what it uses.
>>>>>
>>>>> bp
>>>>> <part15sbs{at}gmail{dot}com>
>>>>>
>>>>>
>>>>> On 3/21/2016 12:47 PM, Josh Luthman wrote:
>>>>>
>>>>> We already stock 5x20mm fuses so keeping with the same form factor
>>>>> would be nice.  Anyone else using those same DIN clip fuse holders have 
>>>>> the
>>>>> same.
>>>>>
>>>>>
>>>>> Josh Luthman
>>>>> Office: 937-552-2340
>>>>> Direct: 937-552-2343
>>>>> 1100 Wayne St
>>>>> Suite 1337
>>>>> Troy, OH 45373
>>>>>
>>>>> On Mon, Mar 21, 2016 at 3:40 PM, Adam Moffett < <[email protected]>
>>>>> [email protected]> wrote:
>>>>>
>>>>>> I have no strong opinions sir, but if it's a replaceable fuse I do
>>>>>> like the automotive blades because every gas station has them.
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 3/21/2016 2:42 PM, Chuck McCown wrote:
>>>>>>
>>>>>> I am considering adding a fuse to a new version of my rack mount POE
>>>>>> surge suppressors.
>>>>>>
>>>>>> I know many of you like PTC resettable solid state fuses.  I don’t
>>>>>> recall ever designing one in to anything.
>>>>>> Maybe I did on a phone device years ago, but that would have been to
>>>>>> satisfy a regulatory agency only.
>>>>>>
>>>>>> Studying up on them I learn that if you have a 1 amp “hold current”
>>>>>> the “always trip” current is 2 amps.
>>>>>> Not like a fuse, which is pretty well guaranteed to trip at any
>>>>>> current over the rating if you wait long enough.
>>>>>>
>>>>>> For a polyfuse, if your load is one amp, you have to have a design
>>>>>> value of greater than 1 amp hold current.
>>>>>> But then it takes double that to actually trip..
>>>>>>
>>>>>> And then there is leakage current required to keep it in the tripped
>>>>>> condition.
>>>>>> It does not totally break the circuit.
>>>>>>
>>>>>> They are fairly inexpensive compared to glass fuses and fuse
>>>>>> holders.
>>>>>> Could do auto blade fuses too.
>>>>>>
>>>>>> Not sure I have the room for anything but a polyfuse though.
>>>>>>
>>>>>> Anyone have strong opinions about this?
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>
>
>
>

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