its realy a matter of safety; using soft start allows you to scale the mains fuse correctly, instead of "chucking in a value that doesn't blow"
manufactured product in europe has to comply with EN61000-3-2 (the flicker factor) which limits inrush currents to stop lights flickering, obviously diy is exempt.
the simplest method of inrush suppression is to use an NTC thermisor in line with the torroid, or two in series if the resistance you want is not available in the current rating you need. 10R is a good starting value for the USA, limiting current to 12.5A.
watch out how you mount these though they run hot (thats how the restance drops)
this type of suppression has one drawback, line dropouts do not allow them to cool and the fuse can blow as the mains dips out for a second and comes back!
manufactured product in europe has to comply with EN61000-3-2 (the flicker factor) which limits inrush currents to stop lights flickering, obviously diy is exempt.
the simplest method of inrush suppression is to use an NTC thermisor in line with the torroid, or two in series if the resistance you want is not available in the current rating you need. 10R is a good starting value for the USA, limiting current to 12.5A.
watch out how you mount these though they run hot (thats how the restance drops)
this type of suppression has one drawback, line dropouts do not allow them to cool and the fuse can blow as the mains dips out for a second and comes back!
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