6 & 8 MOT Stack

6 & 8 MOT (Microwave Oven Transformer) Stack.

I have just finished running my 10" coil from the 8-Transformer Stack for the first time, the results were great, the performance of the coil increased significantly. Spark length increased to about 11-12ft, with the spark intensity also becoming much more intense. The power level has increased from about 8-9kW to around 12kW, The ballast setting was also changed, in order to allow more primary current to flow (Increased from 35 - 55A @ 220V). Hopefully I will get some photos of the coil running at the higher power level soon, however I think I'll leave it a while before I run the coil again, My neighbors must be getting really sick of the noise (It's Really Noisy).

Soon I will post some pictures of 8 Stack.

A 6 Stack MOT power supply has been set up for use with this coil, A dedicated mains circuit has been installed for use by this power supply. While using this supply to run a Jacobs ladder, the un-ballasted current draw from the mains was measured to be 85Amps RMS, The mains voltage dropped to just under 200 volts, giving a total power consumption of 17kVa. To help ensure the microwave oven transformers do not over heat, or are not over stressed by the extra voltage present across them, the are fully submerged under a high grade, detergent free motor-oil. I am aiming at ballasting this to 10kVa for use with the coil (At least initially). Shown in the pictures below, is a current transformer i have made which will be used in the control panel of the system to monitor the current consumption. It will measure from 0 - 100A AC.

This has been cross-calibrated / compared to two other high accuracy digital RMS meters. Initially the no-load current of the 6 Stack was over 12 Amps, I found that by adding 70uF of PF correction capacitors at the input i was able to reduce this back to just over 6 amps. After adding the sliding choke ballast in series with the MOT's the no load current dropped to around 2 amps.