The VARIAC is
a VARIable high power Alternating Current
power supply.
Panel meter show A.C. Voltage and Current.
Voltage is adjustable from 0 to 100% via the Dial between
the meters.
This shows
the panel interior.
The 3 major components are...
1. The Circuit Breaker
2. The Variable phase angle fired Solid State
Controller.(mounted on heatsink)
3. SSC's power supply.