Power supply units of АР and АР-Э series are designed for automatic adjustment of metal remelting procedure in arc DC furnaces of open and vacuum types with capacitance to 30 Tons. Several versions of supply units of different power are manufactured depending on furnace capacitance.

Furnace capacitance is 0.16 to 30 t
Current is 1 to 54 kA
Current adjustment range is 10 to 100%
Current stabilization accuracy is 2 to 3 %

Modern constructions shall be manufactured on the basis of frameworks, permitting to solve ergonomics and aesthetics tasks.

Use of water cooling and powerful new thyristors permits to minimize the supply unit dimensions and floor space occupied.

Microprocessor control system is one of the advantages, that provides the following:

• de-energized melting mode switching;
• optimization of energy input to furnace;
• diagnosis and testing of source status;
• connection with APCS through interface RS-485.

Main functions of control system: 

• Automatic control of energy procedure mode (current stabilization under preset level);
• Dynamic protection against current on-peak loads under unstable furnace operation mode (liquidation of operating);
• Automatic mode of forced current oscillations of hearth electrodes (MFM mixing system) (for open type only);
• Automatic current decrease in furnace on signal “Parasitic arc protection”;
• Current control under automatic arc ignition;
• Automatic electric mode switching (“Modes 1, 2, 3”) under command from furnace control panel from line RS-485 or local panel;
• Limitation of level, effecting mains during dynamic loads in melting process.