On Sat, 20 May 2006 16:23:43 +0200, Zak wrote:
Winfield Hill wrote:
The problem with switching transformer primaries with triacs is
the high inrush current that can develop.
[snip]
There are several solutions, including zero-crossing switching,
or a two-stage switch with a series resistor in the first path,
or both.
It is 'maximum voltage switching' that should be used in this case,
isn't it? Switching on at zero crossing will start with a demagnetized
core handing the full voltage * time integral, where in operation it
would start out with the opposite magnetization.
Thomas
In the early '80's, when I did disco stuff, I controlled neon
transformers by feeding them _complete_ cycles only (using TRIAC's).
I found, from experiment, that partial cycles or an odd number of half
cycles would ultimately smoke the transformer.
...Jim Thompson
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