Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx> Hi Gerry,I run a single gap (2 stationary electrodes are separated and the rotating electrodes pass between this gap where there is a stationary electrode on each side of the disc). I term this a single mechanical gap (2 electrical gaps when ignition occurs). With this type of setup, a large disc is helpful to keep the electrodes away from the motor case. You mentioned the number of gaps as a possible cause. I'm not certain of the mechanism your thinking of there. Dr. R mentioned the number of electrodes as well as a low break cause.
The increase in electrodes or low break have a common probability of preignition of the gap. For example, a situation where a non-ideal low voltage ignition. Because rotary's are narrowly gapped, low voltage ignition is possible, unlike a properly set static gap. The slower the pps or larger the electrode as compared to charge/discharge and quench events, the more likely a power arc might occur.
John Freau mentioned a low C value. That would indicate to me a "very" low C with a fast quench, yet fast enough charge for a preignition while the electrodes are still within range. This may be more likely in a Cres situation where a very high voltage is attained, igniting the gap long before alignment, which would increase the mechanical dwell in relation to the electrical dwell time. I can see how this situation could mesh with Dr. R's experiences.
I wonder if a low voltage (non-ideal) ignition is the root cause to a power arc. And with that, is a non-break-out condition involved in the power arc. I have only speculation, so I'm just thinking out loud.
Take care, Bart Tesla list wrote:
Original poster: "Gerry Reynolds" <mailto:gerryreynolds@xxxxxxxxxxxxx><gerryreynolds@xxxxxxxxxxxxx>Hi Bart,If you dont use a conductive ring, are you going thru 4 or 2 gaps. Im wondering if the number of gaps affects power arcing.Gerry RI have seen it occur on a standard axial electrode arrangement when the pps were too low due to slow motor speeds or too many electrodes.Dr. ResonanceOriginal poster: "Barton B. Anderson" <mailto:bartb@xxxxxxxxxxxxxxxx><bartb@xxxxxxxxxxxxxxxx>Power Arcing Question:Has anyone noticed power arcing with RSG's when a conductive ring is not used? Just curious if this is a side affect contained only to conductive rings on the discs. I haven't experienced it and I don't use conductive rings.Thanks, Bart Tesla list wrote:Original poster: BunnyKiller <mailto:bunikllr@xxxxxxx><bunikllr@xxxxxxx>power arcing is when you really punch up the power and the arc that is created at the disc electrodes and the stationary electrodes continue to transfer electricity even after the spinning ( disc) electrodes have gone past the point of "self exstinguishing" the present arc ... my SRSG employs a copper ring between the 4 disc electrodes and there are pit marks well beyond an inch past the electrode where the hi power arcs have traveled on the copper band..... but then again Im pushing close to 38KV thru my system at full throttle...Scot D