This is a Kema Power SVC-D 10kVA AC Automatic Voltage Regulator used to stabilize voltage fluctuations. [1]
Capacity: It has a power capacity of 10,000 Volt-Amperes (10kVA).
Function: The device protects electrical appliances from power supply fluctuations.
Technology: It is a single-phase servo motor voltage stabilizer, suitable for home and small business use. [1, 2, 3, 4]