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Thanks. There are a few pics of my control panel on PhotoBucket. Being all wood offers some protection. I'm gonna paint it grey, one day. It does have a Danger High Voltage sign on the back. Turning it on involves removing a padlock and turning on the disconnect, turning on the key switch (both keys on the same ring), which powers up the fans, power light, Powerstat actuator, and vfd. Then a toggle switch sends a "run" to the vfd, and a pot controls the RSG speed. The start/e-stop powers the main contactor. Voltage is controlled with an industrial joystick, and speed of the Powerstat actuator is controlled by a pot. E-stop and vfd fault drops out the main contactor. I don't have a dead-man's switch, as I figured I didn't wanna get lonely if I get fried ;) I noticed after posting that my filters are shown on there. I removed my TVSS, as I thought it was rated too low and causing problems. I also only currently use one bombarder slide choke. I had a BIG, several ohm resistor in series with the slide choke, but it caught the wood stand on fire last Halloween after a LONG run. I had to waste a whole beer on it, putting out the flames. Stunk up the garage so bad, I had to open all three doors before doing my "don't try this at home" microwave oven show. I have a fire extinguisher, but know from experience at work, it can be a real b!tch to clean up afterwards. I'd love to build a saturable reactor. I have a 35 kVA 480 to 120/208 three phase dry type transformer I'd like to use, but posts years ago, indicated it couldn't really be adapted using existing windings. I looked into linear actuators to control my slide choke, but never really pursued that. ________________________________ From: Jim Mora <wavetuner@xxxxxxxxx> To: 'Yurtle Turtle' <yurtle_t@xxxxxxxxx>; 'Tesla Coil Mailing List' <tesla@xxxxxxxxxx> Sent: Saturday, August 23, 2014 2:50 AM Subject: RE: [TCML] NIST High Voltage Laboratory Testing / Safety Reference Turtle, Nice layout. My control cabinet (well bonded to ground) is similar though presently I only need one manual power stat. (I have two more off shaft). Its all in a half high 19" rack mount enclosure with a read door. I also use a smaller variac to supply rectified DC to a saturable reactor I pulled from a big Blue Ox oven. I sold the 25KVA monster I used to have. I included a dead man switch on the key switch line. It's just a cotter pin activated microswitch attached to the operator via monofilament and an alligator clip. So if knocked out or worse the system shuts down to protect first responders. I pull the cartridge fuses too, and check for them in my pocket if I'm near the pig. There are interlocks on the doors but as a former support technician in the field, it was always necessary to defeat them somehow to make repairs, schematics on hand. Most of what I did was LV. Some are cleverly well hidden by design engineers. I don't see Tesla Hobbyists as using them unless they have a HV cabinet in the near vicinity. Who would get their head in there without locking out the safety switch? Mine is a Big dude with big knifes and long travel. My electrical is on a big breaker in the main service entrance and feeds a dedicated subpanel near the cabinet. I'm fortunate; my house has all copper water pipe. I use two ground rods at the service entrance in addition and have 3/4 copper feed pipe coming from the water meter near the street under the sprinkler system. It is pretty much a star ground otherwise. RF ground is of course separate and at a distance in the back. Regards, Jim Mora -----Original Message----- From: Tesla [mailto:tesla-bounces@xxxxxxxxxx] On Behalf Of Yurtle Turtle via Tesla Sent: Friday, August 22, 2014 6:43 PM To: Tesla Coil Mailing List Subject: Re: [TCML] NIST High Voltage Laboratory Testing / Safety Reference http://s1050.photobucket.com/user/yurtleturtle/media/Untitled.png.html?sort= 3&o=0 This is my work in progress. I haven't updated it in quite some time. I think the only thing that's missing is the dedicated 100 amp breaker, and the line filters. It's probably not what I would have done from scratch, as it has evolved. Anyway, suggestions/comments are welcome. ________________________________ From: David Sharpe <sparktron01@xxxxxxxxx> To: Tesla Coil Mail List <tesla@xxxxxxxxxx> Sent: Wednesday, August 20, 2014 7:09 AM Subject: [TCML] NIST High Voltage Laboratory Testing / Safety Reference Truly excellent reference for use when designing medium or high voltage equipment or performing HV lab work, from NIST. This document was referenced in a recent EDN e-blog. The great thing about this document is it is succinct, brief (9 pages), specific, and to the point. http://www.nist.gov/el/isd/mmc/upload/high_voltage_rules_revised.pdf One recommendation is the requirement of having "2" separate operations to turn on high voltage; this requires at a minimum a Main Disconnect (Lockable Safety Switch) and a start-stop push-button station with seal in contactor. This requirement supports my contention you should never "instant on" high voltage equipment. YMMV, but I've seen catastrophic, spectacular failures doing this. The additional requirements of a RTZ (Return to Zero) interlock, on all HV equipment is very interesting, and I'd bet less then 5% of the amateur Tesla Coil HV equipment built worldwide has that feature. But RTZ could save your life, and possibly infrastructure too. I am designing a solid state power controller with integral ballasting and current limit regulation (240V/100A) utilizing AC Chopper technology that I have decided to incorporate this feature into the design. An additional requirement is a flashing red beacon with the presence of High Voltage (if it doesn't interfere with testing). If the SG is not firing, you have no outward indication that there is high voltage present, which could have very dangerous consequences. I hope this document is useful to the Tesla Community Best Regards -- Dave Sharpe, TCBOR/HEAS Chesterfield, VA USA Sharpe's Axiom of Murphy's Law "Physics trumps opinion!" _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla