On 5/14/2010 19:00, Seth Mattinen wrote:
> On 5/14/2010 16:42, Ingo Flaschberger wrote:
We had a lightning strike nearby yesterday that looks to have come
inside our facility via a feeder circuit that goes outdoors
underground to our facility's gate.
>>
>> Perhaps there was a "move"
On 5/14/2010 16:42, Ingo Flaschberger wrote:
>>> We had a lightning strike nearby yesterday that looks to have come
>>> inside our facility via a feeder circuit that goes outdoors
>>> underground to our facility's gate.
>
> Perhaps there was a "move" of the earth-level relative to the neutral line
We had a lightning strike nearby yesterday that looks to have come inside
our facility via a feeder circuit that goes outdoors underground to our
facility's gate.
Perhaps there was a "move" of the earth-level relative to the neutral
line.
I have no idea how neutral-line to earth potential is h
On May 13, 2010, at 2:26 PM, Mark Mayfield wrote:
About a month ago, we had a lightning strike near our main campus.
We lost one POE Cisco 3560 completely (apparently blown power
supply), and in a separate but nearby building, another 3560 lost
the ability to deliver POE, but continued to
IMHO,
Long runs of UTP (unshielded twisted pair) make wonderful antenna systems for
EMI and EMP which is why they are matched to differential drivers and receivers
to reject as much common noise as they are designed to. Older and larger
Ethernet interfaces have drivers separated from the logic
On Thursday 13 May 2010 11:36:35 am Caleb Tennis wrote:
> I was just curious if anyone had seen anything similar to this before? Our
> incoming electrical power has surge suppression, and the power to the
> switches is all through double conversion UPS, so I'm not quite sure why
> any of them woul
On 05/13/2010 02:52 PM, Steven Bellovin wrote:
> On May 13, 2010, at 2:24 04PM, Daniel Senie wrote:
>
>
>> While the equipment may well be affected by an EM pulse, if the gear returns
>> to normal after a power cycle, then the equipment vendor didn't do their job
>> fully developing the produc
On May 13, 2010, at 2:24 04PM, Daniel Senie wrote:
> While the equipment may well be affected by an EM pulse, if the gear returns
> to normal after a power cycle, then the equipment vendor didn't do their job
> fully developing the product. A product should be tested to take such pulses
> and
Caleb Tennis wrote:
We had a lightning strike nearby yesterday that looks to have come inside our facility via a feeder circuit that goes outdoors underground to our facility's gate.
What's interesting is that various POE switches throughout the entire building
seemed to be affected in that s
About a month ago, we had a lightning strike near our main campus. We lost one
POE Cisco 3560 completely (apparently blown power supply), and in a separate
but nearby building, another 3560 lost the ability to deliver POE, but
continued to operate as a switch. Both had to be replaced. Both wer
While the equipment may well be affected by an EM pulse, if the gear returns to
normal after a power cycle, then the equipment vendor didn't do their job fully
developing the product. A product should be tested to take such pulses and
should recover provided it has not suffered a catastrophic fa
On 05/13/2010 12:19 PM, Larry Sheldon wrote:
> On 5/13/2010 10:36, Caleb Tennis wrote:
>
>> We had a lightning strike nearby yesterday that looks to have come inside
>> our facility via a feeder circuit that goes outdoors underground to our
>> facility's gate.
>>
>> What's interesting is tha
On 5/13/2010 10:36, Caleb Tennis wrote:
> We had a lightning strike nearby yesterday that looks to have come inside our
> facility via a feeder circuit that goes outdoors underground to our
> facility's gate.
>
> What's interesting is that various POE switches throughout the entire
> building
My first guess would be the lightning was close enough/powerful enough,
to send out an EM Pulse which got picked up by the copper going to the
devices. This EM Pulse may have been interpreted at the switchport as
the device relinquishing power?
Had you tried just unplugging one of the devices from
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