X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from ms-smtp-04.southeast.rr.com ([24.25.9.103] verified) by logan.com (CommuniGate Pro SMTP 5.1.8) with ESMTP id 2038725 for flyrotary@lancaironline.net; Fri, 11 May 2007 18:16:02 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-103-061.carolina.res.rr.com [24.74.103.61]) by ms-smtp-04.southeast.rr.com (8.13.6/8.13.6) with SMTP id l4BMENoQ015743 for ; Fri, 11 May 2007 18:14:24 -0400 (EDT) Message-ID: <000701c79419$fac20120$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: EC2 question Date: Fri, 11 May 2007 18:16:09 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0004_01C793F8.7355E510" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0004_01C793F8.7355E510 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Geeze, Jim. Here I've been using tantalum capacitors in my circuit = boards. Are these failure modes spontaneous or are they triggered by = something like over voltage, over temp, etc. I guess I'm a bit = surprised at the violence of their demise - I would think something like = that would have curtailed their use in electronic circuits. Ed ----- Original Message -----=20 From: James Maher=20 To: Rotary motors in aircraft=20 Sent: Friday, May 11, 2007 5:50 PM Subject: [FlyRotary] Re: EC2 question Al, I would be very careful about adding any tantalum capacitors. Back when I worked as an electronic technician I discovered the = failure mode of these devices. They start off with a little leakage current. As they leak the get hotter. The hotter they get the more they leak. This continues until they build to critical temp and then explode sending a molten projectile 10 feet or more. I actually had some blowup while testing and they burnt a hole in the = floor 10-20 feet away. After that I always made sure that there was a metal cover over the = unit being tested. Just a word to the wise. Jim Al Gietzen wrote: SNIP 47uf, 16V tantalum were added to each processor Pin 8 of connector is now grounded. Pin 28 of connector is now grounded. Al -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_0004_01C793F8.7355E510 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Geeze, Jim.  Here I've been using tantalum = capacitors=20 in my circuit boards.  Are these failure modes spontaneous or are = they=20 triggered by something like over voltage, over temp, etc.  I guess = I'm a=20 bit surprised at the violence of their demise - I would think something = like=20 that would have curtailed their use in electronic circuits.
 
Ed
----- Original Message -----
From:=20 James=20 Maher
Sent: Friday, May 11, 2007 5:50 = PM
Subject: [FlyRotary] Re: EC2=20 question

Al,
I would be very careful about adding any tantalum = capacitors.
Back when I worked as an electronic technician I discovered the = failure=20 mode of these devices.
They start off with a little leakage current.
As they leak the get hotter.
The hotter they get the more they leak.
This continues until they build to critical temp and then = explode
sending a molten projectile 10 feet or more.
I actually had some blowup while testing and they burnt a = hole in=20 the floor
10-20 feet away.
After that I always made sure that there was = a metal=20 cover over the unit being tested.
Just a word to the wise.
Jim

Al Gietzen <ALVentures@cox.net> = wrote:
SNIP
 

47uf, 16V tantalum were added to each processor

Pin = 8 of=20 connector is now grounded.
Pin 28 of connector is now=20 grounded.

Al


--
Homepage:=20 http://www.flyrotary.com/
Archive and UnSub:=20 = http://mail.lancaironline.net:81/lists/flyrotary/List.html

------=_NextPart_000_0004_01C793F8.7355E510--