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

Re: 12KV 750Ma diodes



Original poster: Yurtle Turtle <yurtle_t@xxxxxxxxx>

The ones listed on eBay are $8.50 each for 14 kV 1 amp
ratings. I got these for $20 each. They are rated at
125 kV 1 amp.

http://www.hot-streamer.com/adam/garage/diodes_125_kV_1_amp_1.jpg

They were for use in an x-ray machine, so no need for
potting. Each one has 21 diodes, or 5.95 kV/diode. I
had planned on just buying one and pulling it apart to
make a 29.76 kV 1 amp full wave bridge, but they were
so cheap, I bought four:

http://www.hot-streamer.com/adam/garage/diodes_125_kV_1_amp_2.jpg

Adam

--- Tesla list <tesla@xxxxxxxxxx> wrote:

> Original poster: G Hunter <dogbrain_39560@xxxxxxxxx>
>
> Nah, not a problem.  For one thing, this is how very
> high voltage commercial diodes are built--using many
> smaller elements in series potted in a little brick.
> This is evidenced by the high forward voltage drop
> of
> HV diode modules.
>
> Secondly, when forward biased, each diode in a
> series
> string only drops about .7v.  Multiply this by your
> expected max current of 750ma, that works out to a
> tad
> more than 1/2W per diode.  A 1N4007 at room
> temperature can dissipate 1/2W indefinitely.
>
> Experience-wise, I've had longish series strings of
> 1N4007s last for years in tesla coil power supply
> service.
>
> Cheers,
>
> Greg
>
> --- Tesla list <tesla@xxxxxxxxxx> wrote:
>
>  > Original poster: Mddeming@xxxxxxx
>  >
>  > In a message dated 4/9/07 2:57:58 A.M. Eastern
>  > Daylight Time,
>  > tesla@xxxxxxxxxx writes:
>  > Original poster: G Hunter
> <dogbrain_39560@xxxxxxxxx>
>  >
>  > Here's a pair of 14kv 1000ma diodes:
>  >
>  >
>
http://cgi.ebay.com/HV-Rectifiers-14KV-1-Amp-Set-of-2-HV-Diodes_W0QQitemZ130095517214QQihZ003QQcategoryZ48708QQrdZ1QQssPageNameZWD1VQQcmdZViewItem
>  >
>  > You can also roll your own by soldering twelve,
>  > 1N4007
>  > diodes in series.  This will give you 12kv at
> 1000ma
>  > for under $1.
>  >
>  > Greg
>  >
>  >
>  > Hi Greg,
>  >
>  > Perhaps this is not a problem, but I have always
>  > been concerned about
>  > the power dissipated in long strings of small
>  > diodes. Even a few
>  > volts each, times a dozen or  more diodes, times
> an
>  > amp can generate
>  > some heat. This is probably why I've seen strings
> of
>  > diodes on boards
>  > in oil for some X-ray units. What has your
>  > experience been?
>  >
>  > Thanks,
>  > Matt D.
>  >
>  >
>  >
>  >
>  > ----------
>  > See what's free at
>  >
>
<http://www.aol.com?ncid=AOLAOF00020000000503>AOL.com.
>  >
>  >
>  >
>
>
>
>
>
____________________________________________________________________________________
> Don't pick lemons.
> See all the new 2007 cars at Yahoo! Autos.
> http://autos.yahoo.com/new_cars.html
>
>
>




____________________________________________________________________________________
It's here! Your new message!
Get new email alerts with the free Yahoo! Toolbar.
http://tools.search.yahoo.com/toolbar/features/mail/