Tests no. 1 and 2 show the results of a failure in the recharge system, this happened when both the drive and recharge circuits came on together without protective fusing being used. At this time the system was still being debugged to eliminate a dV/dt problem in the recharge system and may have been the cause of the recharge system to false trigger on. The SCR's in the recharge circuit and some of the SCR's in the drive circuit were totally destroyed in these tests. Tests were continued while changing buckets, adding phase 2 and increasing power levels. The recharge system eventually failed (SCR shorting) in test no. 13 when power levels (di/dt, dV/dt, and I peak specs.) were higher than what the SCR's could take. This test was deliberate to see where SCR failure would occur. Test no. 14 was with the recharge SCR's replaced and was to check out the system before continuing with testing. In these tests one can see apparent gaps between drive coil firings (most noteably the end of phase one). Usually a photo transistor was either out of alignment or taped over causing a loss of an optical trigger pulse. This caused the next firing to be missed because the polarity of the sector capacitor was wrong. However, in phase two some strange things are seen with the first two drive current oscillations. Several oscillations are missing and some come in the wrong place. It was never determined why this took place. Test no. 5 seemed o.k. but as power levels were increased in test no. 6 this effect started, suggesting some sort of unwanted coupling effect between phases or within phase two itself. Phase two was not fully checked out like phase one was due to the earlier mentioned problem of not having sector capacitors for a nine month period.
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