I forgot to bring my second scope home last night but did remember my camera anyway here's a video. All i am doing is switching on and off the power supply. The voltage is set to 142V unloaded using the variac, this is just enough to give me one working cycle of the thyristor before it latches on. So i am cycling the switch on and off, each time i turn on you can see 1 cycle, sometimes when i switch off you can see high current pulses on my secondary but nothing on my primary. The green channel is Chan 1 and this is connected across the secondary, the yellow Chan is 2 and connected across my primary. It's worth noting that my secondary is across my non inductive bifilar which is 0.171 Ohms so for every 5 volt div on the scope we are seeing 29.3 Amps, some of these pulses are +/- 60 amps or more Chan1 is 5V/div Chan 2 is 100V/div and the timebase is set to 10uS/div At first i concentrate on the scope screen, towards the end i focus on the bulb the switch and the scope so you can see how it all fits together. The important point here is that i am not seeing a large primary voltage spike to cause the large secondary current pulses.[youtube]http://www.youtube.com/watch?v=xCcx0SELLOI[/youtube]
« Last Edit: 2011-11-05, 12:35:55 by Peterae »
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