File:Z-machine.jpgZ-pinch at Sandia National Laboratories Z machine. Due to the extremely high voltage, the power feeding equipment is submerged in concentric chambers of 540,000 gallons of transformer oil and 600,000 gallons of deionized water, which act as insulators. However, the electromagnetic pulse generated when discharging the electrical energy to fire the Z machine causes impressive lightning, referred to as "arcs and sparks", which can be seen around all conducting materials in the room.