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Re: ASRSG question

Original poster: "colin heath" <colin.heath4@xxxxxxxxxxxx>

hi there,
            this may seem to simple but if you are grinding flats on your
motor to get it close to 1800rpm or some syncronous speed then here lies
your problem. if it doesnt lock into sync operation then it will perform
terribly and cause major surging possibly adding to the probs you mentioned

----- Original Message -----
From: Tesla list <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Saturday, April 02, 2005 3:31 AM
Subject: Re: ASRSG question

> Original poster: BunnyKiller <bunikllr@xxxxxxx> > > Hey David... > > interesting "problem"... as you know Im running 2 14.4KV 10 KVA piggies > in series for 30+KVAC, my rotory gap is an 1750 rpm motor with milled > flats to run approximately 1800 rpm... my rotor disc is set up with a > copper band around the periphery of the disc and the disc electrodes are in > contact with the copper band. I use only 2 stationary electrodes ( I had > it set up with 4 but the 2 in the rear of the disc wanted to arc to the > motor, which eventually killed it and required a motor replacement). The > rear electrodes were approximately 2" from the motor case, I "thought that > was enuf clearance"... just a thought but I wonder if the magnetic field in > the motor can direct arcs to it quicker than to the ring/rotor > electrodes?? Even tho there is about 1" between the stationary electrode > and the copper band ,there is still a considerable amount of arcing from > the stationary to the band after the rotor electrodes pass the > stationary... BUT I do have to say that the present configuration is alot > smoother than the original 4 stationary method, ,the original 4 stationary > was erratic and "hard to start firing" ... reading your post got me > thinking as to why the older 4 stationary was such a dogged > performer... you would think that if it can jump 1.5"+ on 2 gaps it could > jump .1" at 4 gaps( .4" total) ... > weird.. no answer on that one... the only thing I can think of is > that with the 4 stationary unit the arc direction was "away" from the motor > - to the "inside" rotory electrode - to the outer set of stationary - > thru the cross over bar - back to the second rotory electrode( 180 degrees > apart) - to the "fourth" stationary ( near the motor case) and off to the > primary... the 2 stationary set up is from stationary 1 towards the motor > to the rotory electrode thru the copper band to the second rotory electrode > and out away from the motor to the second stationary electrode.... > > okay that sed... with the 4 stationary arc flow was away from the motor > and the with the new 2 stationary towards the motor.... with the 4 > stationary I had arcs to the motor ( opposite of the desired arc > flow) the 2 stationary is towards the motor as far as arc flow is > concerned.... hope this makes sence cuz I just reread it and now Im all > messed up... :) > > Scot D > > > > Tesla list wrote: > > >Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx> > > > >Hi all, > > > >I have noticed a problem with the ASRSGs that I have built. I think > >I may have already mentioned this a few years ago and IRC, it was > >sort of a mystery then. The problem is that when I make a rotary > >gap of the dual gap style (2 pairs of stationary electrodes placed > >180 degrees apart along the periphery of the rotary disc so that > >each time that it fires, the discharge goes through 2 rotary elec- > >trodes instead of 1). Is that clear as mud? Anyway, when I try to > >run my ASRSGs like that, it will not fire no matter how close the > >rotary electrodes pass to the stationary electrodes or if it does > >fire, it fires very erratically and ends up smoking something in > >the control panel (I blew out a 1000 volt, 50 amp FWB rectifier > >brick for the DC motor of my RSG last time)! In the past I was > >able to rectify this issue by either going with a single rotary gap > >or if I kept it double series, I had to use a motor with a double shaft > >and keep both sets of stationary electrodes on the same side of the > >motor. Does this make any sense? Also, I've noticed that SYNCHED > >rotary gaps don't seem to have this problem with running double > >rotary gaps 180 degrees apart. Can anyone tell what gives with this? > >The only reason that I was thinking of using a double-seriesed ro- > >tary gap is that I will be pushing up to 15 kVA with my latest > >Tesla system and that will produce considerable heat at a single > >contact point. > > > >Also, I've changed secondary coil from a 12.5" x 44" long wound w/ > >900 turns of #17 magnet wire to a 12.75" x 48.5" long wound with > >1260 turns of GREEN # 19 magnet wire. I think that #19 is still > >large enough wire for this and I know the 1260 turns is a better > >number of turns than 900, keeping in the 1000 to 1500 turn range. > >That will be a better choice for secondary coil for a 15 kVA coil with > >a 12x56 toroid. I have a 0.2 uFD primary capacitor and a 15 kVA, > >14,400 volt PDT to power it. Actually, I have (2) 15 kVA PDTs so > >so I could series the PDT outputs for nearly 30 kV!.Of course, I > >would then have to series instead of parallel my (2) Hipotroncs 0.1 > >uFd, 50 kV pulse caps for a 0.05 uFD, 100 kV assembly instead of the > >0.2 uFd, 50 kV configuration that I now have. My rotary electrodes are > >(8) each 1/2" x 2 1/2" long tungsten carbide drillling blanks and my > >stationary electrodes are (2) each 1/2" x 3" long tungsten carbide > >drilling blanks mounted in 2 1/2" long, 1.25" brass square stock. > >Actually it WAS (4) stationary electrodes but now is (2) due to > >the problem that i mentioned above in the first paragraph :^) Any > >comments are welcome. > > > >David Rieben > > > > > > > >