[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: power factor correction capacitors (fwd)



---------- Forwarded message ----------
Date: Mon, 02 Jul 2007 12:32:13 +0000
From: David Rieben <drieben@xxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Cc: drieben@xxxxxxxxxxx
Subject: Re: power factor correction capacitors (fwd)

Hi Scott,

Check this out:

http://cgi.ebay.com/New-100UF-100-UF-RUN-OIL-CAPACITORS-CAPACITOR-370V_W0QQitemZ170124898221QQihZ007QQcategoryZ4662QQrdZ1QQcmdZViewItem

These make excellent PFC caps and have a realtively high capacitance
so that you would only need 3 of them to achieve your desired 295 uFd
(you'd actually exceed it by 5 uFd, which is close enough). Also, their 370 
VAC rating allows them to be used with either 120 or 240 volts without
worry of overvolting them. I have personally purchased these capacitors
before and they are a great capactior for the money.

David Rieben

-------------- Original message -------------- 
From: "Tesla list" <tesla@xxxxxxxxxx> 

> 
> ---------- Forwarded message ---------- 
> Date: Sun, 01 Jul 2007 21:57:59 -0400 
> From: Scott Bogard 
> To: tesla@xxxxxxxxxx 
> Subject: Re: power factor correction capacitors (fwd) 
> 
> Considering that I don't get to the junkyard everyday (sadly), and since DC 
> capacitors are relatively cheap for their voltage/capacitance rating, could 
> I use two parallel strings of DC caps, each protected by a diode to keep the 
> power flowing the right way, or would this not work (or if I grounded the 
> strings)? For my power supply, Java TC is suggesting I need a 295 uf cap 
> size, and considering how low the values of motor run capacitors generally 
> are, I would need a whole lot of them! Thanks. 
> Scott Bogard. 
> 
> 
> >From: "Tesla list" 
> >To: tesla@xxxxxxxxxx 
> >Subject: Re: power factor correction capacitors (fwd) 
> >Date: Sun, 1 Jul 2007 17:25:04 -0600 (MDT) 
> > 
> > 
> >---------- Forwarded message ---------- 
> >Date: Sun, 01 Jul 2007 12:33:25 -0400 
> >From: David Speck 
> >To: Tesla list 
> >Subject: Re: power factor correction capacitors (fwd) 
> > 
> >Scott, 
> > 
> >IMHO, it's not worth it to try to build a PFC cap. You can get metal 
> >can (oval or round) oil filled motor run caps for free from dead air 
> >conditioners, refrigerators, some furnaces, or dehumidifiers at your 
> >local recycling center. Usually, the bigger the original device, the 
> >bigger the cap. They are also available from eBay. Even microwave oven 
> >caps work, but at only 1 uF each, you would need several in parallel. 
> >Motor run caps will have a definite capacitance value, like 6 uF at some 
> >voltage, stamped into the case. 
> > 
> >Do not use round black plastic encased electrolytic motor start caps -- 
> >they are intended for a duty cycle of only a few seconds, and get hot 
> >and explode if run continuously. Start caps usually have a very wide 
> >range of capacitance printed on the case, like 50 - 120 uF at some 
> >voltage. 
> > 
> >Dave 
> > > Hey everybody, 
> > > Can anybody tell me where I can get, some capacitors to use for 
> >power 
> > > factor correction (and how much it would cost me)? Would it be insanely 
> > > difficult to build one? Could I use motor start or run capacitors? 
> >Thanks. 
> > 
> > 
> > 
> 
> _________________________________________________________________ 
> Need a break? Find your escape route with Live Search Maps. 
> http://maps.live.com/default.aspx?ss=Restaurants~Hotels~Amusement%20Park&cp=33.8 
> 32922~-117.915659&style=r&lvl=13&tilt=-90&dir=0&alt=-1000&scene=1118863&encType= 
> 1&FORM=MGAC01 
> 
> 
>