ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
What does your work place look like?
by Bill Addiss - 11/23/20 12:07 AM
Where is Everyone?
by Lostazhell - 11/21/20 04:17 AM
Ground fault remover :-)
by dsk - 11/21/20 02:47 AM
Work Gloves?
by gfretwell - 11/20/20 10:17 PM
Reverse-feeding transformer in PV system?
by winnie - 11/19/20 06:49 AM
New in the Gallery:
Facebook follies, bad wiring
FPE in Germany pt.2
Who's Online Now
0 registered members (), 18 guests, and 14 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
Bulging Capacitors #193020 03/16/10 12:24 AM
Joined: Mar 2008
Posts: 76
P
packrat56 Offline OP
Member
This is actually something I got to see firsthand after an old computer I had did an auto-shutdown due to an overheated CPU. I thought it was the fan at first, but the fan still works so my next guess was dust causing hot spots in the heat sink. I then noticed some capacitors on the motherboard were bulging, the way I understand it is that a budging capacitor can mean the component is close to failure.

What causes this to occur? Is it just normal wear or does it has to with abnormal voltages?


I have a sense of adventure, I just keep it leashed with common sense.
Tools for Electricians:
Re: Bulging Capacitors [Re: packrat56] #193021 03/16/10 12:30 AM
Joined: Mar 2008
Posts: 76
P
packrat56 Offline OP
Member
Strange, the motherboard to my old windows 98 has now outlasted the motherboard for a windows Xp.

Last edited by packrat56; 03/16/10 12:30 AM.

I have a sense of adventure, I just keep it leashed with common sense.
Re: Bulging Capacitors [Re: packrat56] #193023 03/16/10 12:52 AM
Joined: Mar 2004
Posts: 251
W
WESTUPLACE Offline
Member
I replace lots of bad caps on motherboards. Most will split and leak out the top. I work on security DVRs. They use a standard motherboard, different brands, all have shown failure in the electrolytic caps. Different problems will develop, depending on what failed. Take a good soldering iron and great care but they can be replaced. Most are 6.5v 1000, 1500 or 2200uf. If your computer is running slow or has booting problems, check the caps. I have replaced 50 or more last year. Most of these machines run 24-7, which may be why I see so much failure. They also fail on video cards. Sometimes its cheaper to buy a new card than replace the caps. Robert

Re: Bulging Capacitors [Re: WESTUPLACE] #193025 03/16/10 01:13 AM
Joined: Mar 2008
Posts: 76
P
packrat56 Offline OP
Member
Thanks WESTUPLACE, but unfortunately when I tried to pull the fan off to check the heat sink I didn't release the lock-tabs and it took the heat sink and the CPU with it. One of the pins on the CPU got bent when I tried to put the CPU and heat sink back in.

I'm thinking that the oveheating of the CPU may somehow be connected to the capacitors bulging.

Last edited by packrat56; 03/16/10 01:16 AM.

I have a sense of adventure, I just keep it leashed with common sense.
Re: Bulging Capacitors [Re: packrat56] #193028 03/16/10 12:18 PM
Joined: Mar 2005
Posts: 1,213
S
SteveFehr Offline
Member
Electrolytic capacitors are a failure item, they simply have a finite life span and eventually fail. Failures typically start to occur at around 5 years, but it depends on a lot of things- ambient conditions, power quality, etc.

Re: Bulging Capacitors [Re: SteveFehr] #193060 03/17/10 08:14 PM
Joined: Mar 2005
Posts: 1,803
Alan Belson Offline
Member
Bigger capacitors can also fail in this way. Here's a 60uf from one of a pair of 3 hp single-phase motors running a 440v 3-phase generator. It had been getting a hammering when I let a couple of bozos loose on a big planer as a favor. They kept stalling and restarting it, too stupid to grasp the concept of a mechanical starting clutch. This was the result, [2007 pic]:

[Linked Image from electrical-photos.com]

I fitted a new cap, no visible smoke let out! The other motor was apparently undamaged by the incident. Both have continued to run OK for the last couple of years .


Wood work but can't!
Re: Bulging Capacitors [Re: Alan Belson] #193062 03/17/10 08:36 PM
Joined: Mar 2005
Posts: 1,803
Alan Belson Offline
Member
Here's my set up, duplex 230v 3 hp motors running a 440v 3 phase generator with 1:1 vee-belt drive.

[Linked Image from electrical-photos.com]

[The planer will not start, even with star delta, on 6hp gross output - it's a 20" beast with a 70 lb cutter block running @ 4500 rpm. I fitted a foot operated-clutch to ease her up to speed. The motor is 7.5hp, but I restrict the power by taking lighter cuts.]



Wood work but can't!
Re: Bulging Capacitors [Re: Alan Belson] #193063 03/17/10 09:10 PM
Joined: Feb 2003
Posts: 939
F
frenchelectrican Offline
Member
The way you describe the planer that is pretty good size unit I have a 16 inch unit but unforetally it is not a electrique unit it is diesel driven but I put in a shear bolts in case someone jammed with hardwood and stall it.

{ it did happend couple time allready }

I know how long it take to get up to the running speed and I have one of my customer he have very serious sized planer IIRC it will take up to 48 inches that one have 2 motors in there one for planer head the second motor for feed drive { that one is a DC motor } the planer motor itself is 30HP that thing really screams once it get up running speed.

Merci,Marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Re: Bulging Capacitors [Re: frenchelectrican] #193064 03/17/10 09:44 PM
Joined: Mar 2008
Posts: 76
P
packrat56 Offline OP
Member
Gee Alan, that was a motor starting capacitor? I didn't know it could happen in commercial capacitors.


I have a sense of adventure, I just keep it leashed with common sense.
Re: Bulging Capacitors [Re: packrat56] #193073 03/18/10 09:16 AM
Joined: Mar 2005
Posts: 1,803
Alan Belson Offline
Member

Here's my post from April 2005 describing some of my machines, which are almost all renovation projects.

My memory is not what it was, and I got some of the details wrong, it's a 6kw alternator.

The Robinson planer was bought to France in about 1992 after our work's carpentry shop closed down in the recession at that time. Funnily enough, I also originally ran it with a small diesel engine till I made an electrical conversion in 2004/5. The main problem was smoke from the stub exhaust and the noise - it was a hand cranked single cylinder job out of a Chinese tractor! Still got it [somewhere].

https://www.electrical-contractor.n...e_built_alternator_Some_.html#Post120645

Last edited by Alan Belson; 03/18/10 09:25 AM.

Wood work but can't!
Page 1 of 2 1 2

Featured:

2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
Attic Rat
Attic Rat
Bergen Co.,N.J. USA
Posts: 524
Joined: December 2003
Show All Member Profiles 
Top Posters(30 Days)
Trumpy 9
Popular Topics(Views)
271,873 Are you busy
205,730 Re: Forum
193,832 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3