Spellman DXR3000/LC -- Help??

This forum is for specialized infomation important to the construction and safe operation of the high voltage electrical supplies and related circuitry needed for fusor operation.
User avatar
Richard Hull
Moderator
Posts: 11368
Joined: Fri Jun 15, 2001 1:44 pm
Real name: Richard Hull

Re: Spellman DXR3000/LC

Post by Richard Hull » Mon Jun 05, 2006 9:23 pm

Faster recovery diodes would be a bit better the 1000 volt
UF1007DICT-ND (digikey #) has a 75 nsec recovery and are $29.00 per 100 diodes. I use these exclusively now. I am not sure how series connections will affect the recovery time but it shouldn't lengthen by too much.... Certainly not as bad as a string of IN4007 which hang around 500 ns recovery.

Too bad Schottky Barrier diodes can't seem to crawl out to the 1000 volt level, Those babies are really fast. ( ~4ns) At this speed, however, circuit layout is critical to retain the speed figure and not much switching at both high voltage and high power occurs at frequencies where these work. There might come a day though..........

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

Richard Hester
Posts: 1458
Joined: Thu Jul 05, 2001 4:07 am
Real name:

Re: Spellman DXR3000/LC

Post by Richard Hester » Mon Jun 05, 2006 10:38 pm

Actually, the standard 1N4007 diodes will be more like 2 usec recovery time if you are lucky. Cheaper brands may be worse. If you actually ask them to recover form a large forward conduction pulse, performance may be worse.

DaveC
Posts: 2346
Joined: Sat Jun 30, 2001 5:13 am
Real name:

Re: Spellman DXR3000/LC

Post by DaveC » Mon Jun 05, 2006 11:28 pm

Right! Which is why you should be very conservative in rating them. Still, for power frequency operation, especially if you have some output filtering, they should be okay. But if one suffers a voltage collapse, it might precipate failure of others, if you're running too far up towards rating limits.

But there's no question, the faster recovery diodes will be more robust, and better all around. It's just, that when you have 'em and you're on a limited budget, you learn how to make it work, till you can afford to upgrade.

And again... be careful.. these are good for about an ampere average and probably have ~100A transient current capability. They won't act like a fuse till you're in serious trouble, if you inadvertently become part of the output circuit.

Dave Cooper

DaveC
Posts: 2346
Joined: Sat Jun 30, 2001 5:13 am
Real name:

Re: Spellman DXR3000/LC -- Help??

Post by DaveC » Fri Jun 16, 2006 8:43 pm

Now your fun begins.....

Depending on how improvised you want your setup, anything that produces AC at a reasonably high frequency will drive the multiplier. Not sure what frequency that unit was designed for, but assume 20 kHz or somewhat higher. For low voltage and lowpower testing you can drive it with an audio oscillator and amplifier.

The multi-pin connector shouldn't be too hard to sort out, since it primarily will return back voltage, avg current and surge/fault signals to the controller. The larger LV leads, are where the AC goes in.

Have fun, and may all your grounds be solid.

Dave Cooper

cwarner
Posts: 1
Joined: Thu Jul 27, 2006 3:10 pm
Real name:

Re: Spellman DXR3000/LC -- Help??

Post by cwarner » Thu Jul 27, 2006 4:01 pm

I have three Spellman units available. I have not powered the units up, or tested in any way. Please call or email if you want images or further info. I am accepting offers for the units.

Spellman DXR 3000A INV.
Model DXR3000A/WSF/FSI/PH/LC


Spellman DXR 3000A FIL
Model DXR3000A/WSF/FSI/PH/LC


Spellman DXR 3000A HV
Model DXR3000A/WSF/FSI/PH/LC
Attachments
DSC02080.JPG
DSC02080.JPG (583.76 KiB) Viewed 3455 times

wayne
Posts: 40
Joined: Mon Apr 10, 2006 7:45 pm
Real name:
Contact:

Re: Spellman DXR3000/LC -- Help??

Post by wayne » Thu Aug 03, 2006 1:06 pm

I just received the DXR3000 from Casey Warner. One unit is the same as
yours, the second unit has the transformer and diode stack with a voltage
reference circuit. The third seems to add fill. power. One HV input and a
three pin HV output.
I ordered the $100.00 manual and will loan it to anyone having a need.
We are replacing the frayed wires and after we get the manual, at a
safe distance, the smoke test is in order.

wayne

nemesistech
Posts: 64
Joined: Thu Jul 26, 2007 2:17 pm
Real name:

Re: Spellman DXR3000/LC -- Help??

Post by nemesistech » Fri Aug 10, 2007 5:54 pm

Would love to take a gander at this manual as well, just bought the "rack and stack" 3000 as well, just waiting for it to arrive.
Attachments
spellman-3000-dx-0731.jpg
spellman-3000-dx-0731.jpg (413.78 KiB) Viewed 3455 times

User avatar
Richard Hull
Moderator
Posts: 11368
Joined: Fri Jun 15, 2001 1:44 pm
Real name: Richard Hull

Re: Spellman DXR3000/LC -- Help??

Post by Richard Hull » Fri Aug 10, 2007 8:36 pm

I was curious about this, but just had a bad feeling. I could easily have driven to their door and picked it up, too, as I constantly visit a friend only a few miles from Sykesville, MD. There is a quaint railroad restaurant there that is worth visiting.

Let me know how this works out. If it is good and complete, I will kick myself.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

nemesistech
Posts: 64
Joined: Thu Jul 26, 2007 2:17 pm
Real name:

Re: Spellman DXR3000/LC -- Help??

Post by nemesistech » Wed Aug 29, 2007 9:53 pm

It is a complete system, all cables, etc. Everything powers up fine, but I am still working around the filament chassis and it wiring, and how either to bypass it or exclude it... (thanks to Jon for his help) The only thing that was damaged was the coolant tank which I dont need.

MarkS
Posts: 250
Joined: Sat Jun 30, 2007 8:07 am
Real name:

Re: Spellman DXR3000/LC -- Help??

Post by MarkS » Thu Aug 30, 2007 4:53 am

Its ok Richard I'm kicking myself up here in Fairfax for not getting it as well.

Post Reply