UNIBOX Series Medium‑Voltage Motor (Fabricated Frame)

The UNIBOX Series is a heavy‑duty rugged large frame motor series designed in South Africa for applications in power stations, mining and heavy industrial sectors. The design is suitable for both squirrel‑cage and slipring induction motor formats. UNIBOX motors are available in all standard motor shaft heights from 355 mm to 1000 mm with international standard foot or flange fixing arrangements. Output ratings are designed to suit client specific requirements up to 15 MW. Windings are designed as standard for 3.3 kV, 6.6 kV, 11 kV and 15 kV at 50 Hz, with other international voltage supply standards available on request. The motor is electrically and mechanically designed in accordance with IEC 60034. The standard enclosure is IP22 IC01 (drip‑proof), with other protection levels (IP55, IP65) and cooling methods (air‑to‑air, air‑to‑water) available. The UNIBOX motor features a robust, box‑type, heavy gauge mild steel plate fabricated frame, with stress‑relieved welded construction. The stator core uses low‑loss, non‑grain oriented silicon steel laminations, and the stator windings are vacuum pressure impregnated (VPI) using a solventless epoxy resin for void‑free insulation. The motor is available with either grease‑lubricated rolling element bearings or oil‑lubricated sleeve bearings, with calculated design bearing life (L10h) of not less than 40,000 hours. The UNIBOX is designed for low noise levels and high efficiency, with achievable vibration levels of grade "B" limiting values given in IEC 60034‑14.