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Hoffman Amps Forum image Author Topic: Wall power inrush current limiter and filter  (Read 2186 times)

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Offline NSB_Chris

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Wall power inrush current limiter and filter
« on: March 28, 2019, 08:25:12 pm »
Does anyone bother with adding a filter (0.1uF) cap across the AC mains leads and a current limiting thermistor on the neutral lead?  I see this on some of the more modern schematics.  The amps I have built so far were vintage clones and I just ran the AC input straight through the switch and fuse to the PT.  Anyone think it is worth the extra trouble?

Offline shooter

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Re: Wall power inrush current limiter and filter
« Reply #1 on: March 28, 2019, 09:01:38 pm »
at the top of this page there's a search, had a pretty good discussion ~~1yr ago?
Went Class C for efficiency

Offline NSB_Chris

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Re: Wall power inrush current limiter and filter
« Reply #2 on: March 28, 2019, 09:16:09 pm »
Can you provide a link to the thread that you are referring to?  I did a google search earlier and just tried to search this forum but I don't seem to find anything directly on topic. 

Offline shooter

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Re: Wall power inrush current limiter and filter
« Reply #3 on: March 29, 2019, 09:37:46 am »
this isn't the one I was thinking, but it has links to "fixes"
http://el34world.com/Forum/index.php?topic=23036.msg246947#msg246947

most forgo any fancy wiz-bangs.  I have put .1uF on the left side of bridge, even used them on the right side  :icon_biggrin:.
I believe ppl have tried MOV's, step start etc. at the end of day they probably do little and provide yet another thing that can break
Went Class C for efficiency

 


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