I Built and Used My First Incandescent Bulb Current-Limiter
Ralph Barone wrote:
=================
Section 4 of your linked article talks about transformer inrush, which is a
definite concern for equipment with large power transformers. We had an
event a couple years ago when energizing some 500 MVA, 500 kV transformers
at the wrong point on wave resulted in a large outage and actual
destruction of some other equipment in the vicinity.
** Be like bomb going off.
FYI:
Transformers a *lot smaller* can be a problem also.
1. Any toroidal power transformer of 800VA or more rating will regularly trip a household breaker at switch on.
2. A 1kVA conventioal job will do the same.
3. 40uF of AC rated film capacitors on the same switch will do it too ( for 240VAC power) .
4. Ditto for 2 or more colour CRT screens switched together.
Each of the above cause 150A peak surges that trip the magnetic part of the breaker.
...... Phil
|