Hi Jan-Martin,
Nicely wound toroids. I'd just be careful with 40KV. Even a Teflon
coated wire with about a millimeter of insulation thickness is usually
not rated nearly as high.
In medical electronics you have to certify all components in the "strike
path" to withstand a certain voltage. In our case mostly about 5KV
because that is the charged-up voltage of a defibrillator. Believe me,
if you need to transfer sensitive signals it is very tough to create an
isolation that holds this voltage level safely for extended periods and
will be blessed by the agencies. The latter is the hardest part
Regards, Joerg
Joerg
Well, I had some particular projects at work at Norwegian telecomm and
was working on some ideas to protect the telecommunication equipment,
and in many instances it worked out with very little sync-loss
compared with doing nothing. In one instance I reduced 5000
sync-losses in 24 hours to 3 bit-losses in 4 days.
Anyway, it has been some work on lightening, and in telephone lines on
cables it is unlikely that lightening voltages are higher than 35kV,
but the limit for our test equipment was 40kV, so we didn't know what
the transformers could stand.
I agree with the points you mention, but the normal line transformers
- wound with magnet wire and no steps are taken to avoid damage if
stuck by lightening breaks down somewhere around 4-5kV, so the
addition of an extra transformer you believe stands 40kV might be an
improvement, but in some cases it don't.
In our case, we solved some equipment and made many customers happy -
at least the error bits and sync-losses were minimized
Jan-Martin
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