Inrush current limiters ( ICLs)

[Robert Groh]

I have started to do add inrush current limiting protection on almost all my restorations.  Particularly when I convert to solid state rectifiers and principally to cut down the huge current surge charging up the filter caps.  With a vacuum tube rectifier, you have the tube warm up time and characteristics which 'soften' the charging.  Not the same with solid state rectifiers - you get full rectified voltage pretty much right on turn on.  And, of course, softening the surge due to the filaments coming up to voltage doesn't hurt either.

Mouser has a couple of vendors supplying inrush current limiters:
<http://www.mouser.com/catalog/catalogUSD/638/590.pdf>
and
<http://www.mouser.com/catalog/catalogusd/638/588.pdf>

If you follow the path through the Mouser site, you can find a link to the data sheets et al.  I think it is pretty good insurance.  With today's higher AC line voltages, we certainly have extra line voltage to burn.  Although adding a buck transformer to drop the line voltage would probably be a very good idea.  I haven't done that yet.

73
Bob, WA2CKY




________________________________
From: Bob Jackson <bob at NOFROWNS.NET>
To: BOATANCHORS at LISTS.TEMPE.GOV
Sent: Monday, June 29, 2009 10:38:42 AM
Subject: [BOATANCHORS-TEMPE] Inrush current limiters ( ICLs)

When restoring BAs (or any other vintage radio), is anyone here installing ICLs to protect tube filaments, etc.? I haven't been but am considering using small value thermistors for that purpose. My interests lie mainly in entry-level comm. radios a la Halli S-120 and similar.

Thanks,

Bob
AG5X

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.aspx?list=BOATANCHORS
To post - BOATANCHORS at LISTS.TEMPE.GOV
Archives - http://lists.tempe.gov/archives/BOATANCHORS.html

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.aspx?list=BOATANCHORS
To post - BOATANCHORS at LISTS.TEMPE.GOV
Archives - http://lists.tempe.gov/archives/BOATANCHORS.html