Joe,
On 21/03/14 16:17, Joe Gwinn wrote:
Magnus,
Thus, another fairly severe environment.
I have a personal war story from 1992: At a Air Traffic Control center
in Canada, one 19" cabinet had the green (safety ground) and white
(power neutral) cables transposed. This caused 2.3 Vrms at 180 Hz to
appear between the VMEbus ground and the cabinet shell, with enough
oomph to cause a small spark when oscilloscope probe grounding clip was
connected to that VMEbus ground, this causing the system (and my heart)
to crash. If left connected, the ground clip became warm. And how can
ground generate a spark, even a small one? Fixing the grounds dropped
the offset to around ten millivolts. The 180 Hz arose because the
power supplies were single-phase capacitor-input, driven from the legs
of three phase prime power.
Power neutral isn't really neutral when it takes a lot of beating.
Similarly, a grounding wire isn't doing much grounding as frequency goes up.
That fails economically - might as well stick to IRIG.
Indeed. Doing 1 us level might be possible, going lower than that will
cause you more and more grey hairs one way or another.
Well, now, this could be an advantage -- my hair is already gray, and
more could be better.
Well, you may have younger colleagues which fails to have this
advantage. I knew you would make the comment. :)
There is a truism in the standards world, that it take three major
releases (versions) of a standard for it to achieve maturity. PTP is
at version 2, so one more to go.
I'd say it depends on for what application. The trouble is when the
assumed applications increase at a quicker rate than the standard adapts
to handle them.
It does, but having the market grow faster than the standards cycle can
be the mark of success.
To some degree. Being perceived to be a solution isn't the same as it
being a solution.
By the way, development of the third revision of 1588 started in 2013.
I joined what purported to be their reflector, but now that you mention
it I haven't gotten any traffic -- Something must be wrong. I will
need to enquire.
They formally had their first session at the ISPCS in Lemgo.
Cheers,
Magnus
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