Re: Another MMC cap candidate (UK)
On Mon, 21 Jun 1999 16:57:18 -0600, you wrote:
>Original Poster: Alan Sharp <AlanSharp-at-compuserve-dot-com>
>I just tried out a string of the 0.047uF 1500V DC caps
>in parellel with my existing 0.067uF cap.
>The transformer is 8KV DC, 250mA
>The coil frequency is 200kHZ.
>I started with 8 in series no problem, went down to
>6 and ran for over a minute with no apparent heating.
>I then tried 5 but I stopped the run when I thought I
>saw a flash from one of the caps - no apparent damage though.
>The caps are film and foil polypropylene, axial construction.
>pulse rated at 2000 V/uS.
>Made by LCR, available from Farnell (code 106-372)
>5+ 46p (70cents) 25+ 40p, 100+ 35p, 500+ 32p
>I'm also using 10M equalising resistors, rated for 2500VAC (.5W)
>metal glazed. 10+ 16p, 300+ 11p,
>Farnell code (341-850)
>I'm probably going to use 8 in series for safety, and build 2, 8 by 8 caps
>I'll put off purchasing these in case any one has ideas on
>how to get them cheaper.
Farnell are unlikely to be cheapest for anything - I'm told they
usually work on a 50% markup! For the best price, you usually need to
go to a specialist distributor. Don't expect credit card facilities,
and expect to have to by a minimum quantity (i.e. a boxful). If you
pretend to be a consultant for a company planning to buy lots in
future they will take you more seriously. Also check their delivery
charge - many distributors only use couriers and can cost up to 15
My 1996 distributor directory lists the following distributors for
Bloomer 01762 339818
C&CD 01494 882848
Cholcraft 01202 874455
Greenwood 01734 333788 (NB I think this Reading dialling code has
Livewire 01291 673003
Newsham 01772 863553
SSS 01892 836836
A more recent CD-ROM index lists :
Carlton Distribution 01733 559015
Cholcraft (as above)