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Old August 20th 08, 10:02 AM posted to rec.radio.amateur.homebrew
Andrew VK3BFA[_2_] Andrew VK3BFA[_2_] is offline
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First recorded activity by RadioBanter: Sep 2007
Posts: 24
Default Sending power into rig unused for 30 years : Precautions ?

On Aug 20, 8:27 am, (Edmund H. Ramm) wrote:
In Andrew VK3BFA writes:


There will only be negligible inrush current limiting. For that you'll
need an NTC resistor like an Epcos NTC22. All you get from a light bulb
is a voltage reduction -mains voltage minus the voltage drop across the
bulb- but only AFTER the inrush current you intended to prevent has already
flown.

A light bulb in series with an inrush current limiter might be suitable
for smoke testing equipment after prolonged disuse, though.


Yes. Whats the DV/DT of the positor versus a light bulb? - I got no
idea.....
The light bulb method works - its quick and dirty, and so far I have
never blown an electrolytic capacitor using this method. Its also VERY
useful in firing up SMPS devices - it does current limit quick enough
if theres a gross fault to prevent damage.

But, each to his own. Of more concern would be corrosion /freezing of
pots/switches etc. And a 30 year old mains power cable? - mm - and
what about checking the insulation resistance of the power
transformer..

But it ain't the Space Shuttle - live dangerously...Just Do It....

Andrew VK3BFA.