Steps 13 and 14
Step 13: Tesla Coil Setup Rules
We are now ready to power test the coil! Before we do so, we want to do some final checks. Reference this step before each time you run the coil.
- Make sure the breakout point is installed. Failure to do so will result in a Tesla coil that is unable to discharge itself, causing high currents to build up in the driver and likely damage to the bridge.
- Make sure the Tesla coil is running in the proper environment. DRSSTCs are very sensitive to their environment, as running on a poorly grounded surface or too close to conductive objects results in altered toroid capacitance and a shift in the tuning point. The best place to run a TS is on a floor away from other objects. If you’re running on a table or unsure about the ground situation, place a sheet of aluminum foil or aluminum window screen below your coil. You can even cover the conductive plane with a cloth to improve its aesthetics! Just be sure to use an alligator clip to connect the coil’s heat sink to the conductor.
- Ensure that the outlet you are connected to has good grounding (this means no portable generators, inverters, or 2-pronged outlets).
- Make sure that you are spacing yourself, your interrupter, your MIDI device, and any other sensitive electronics the full length of the optical fiber from the coil (10 feet minimum).
- Persons with pacemakers or other medical implants should not be in the vicinity of the coil.
- Always start at minimum power and ramp up slowly. This makes it easier to catch problems without damaging the coil.
- If you are using a laptop as a MIDI source, make sure it is not plugged in, or, if it is, make sure it is plugged in to an isolated adapter. Do not use a desktop computer to control the coil.
- The Tesla coil is tuned to operate best in a standard environment which we feel is typical of the conditions most users will operate it in. Some variation moving from location to location is expected.
- The radiated electric field has a tendency to temporarily cause nearby capacitive touchscreens and laptop touchpads to misbehave. This is normal, and will not permanently damage your electronics. If this happens, just move further away from the coil.
Step 14: Startup and Shutdown Procedure
- A. First, verify that your interrupter is behaving normally. Look into the output of the fiber transmitter and verify that the output is behaving as you expect it to.
- C. Distance yourself the full length of the optical fiber away from the coil. Power up the interrupter on LOW power, and watch the coil carefully for any problems as you slowly turn up the power.
If this is your first time powering up the coil...
- D. In Fixed Mode on the interrupter, press and hold the [Up] button to set the frequency to 1000Hz (the maximum). We recommend a high frequency for a first test because higher frequencies draw less power from the coil.
- E. Press [Select] to switch to Power control, and then [Up] to slowly increase the power. Watch the secondary for flashover, and make sure the tone being emitted by the coil stays clean-sounding.
- F. Turn off the interrupter, then unplug the coil. Wait 5 minutes before servicing the board to let the bus capacitors discharge.
Every time you turn on the coil
Reference this startup procedure every time you turn on the coil!
Every time you turn off the coil
To turn off the coil, FIRST cut the interrupter signal first, THEN cut AC power. Cutting off the coil from AC power while the interrupter is still sending a signal can cause indeterminate states in the logic circuitry as the voltage rails sag, and can blow your IGBT bridge!