Medium-voltage drive for 3.3 kV motors
The Schneider Electric ATV1200A8605555 is an Altivar 1200 medium-voltage variable frequency drive rated for 860 kVA apparent power and 719 kW motor output. It accepts a supply voltage of 2970 to 3630 V, placing it squarely on 3.3 kV class grids — common for large pumps, fans, and compressors in mining, water, and heavy industrial plants. The input stage uses a 30-pulse diode rectifier bridge, which cancels the 5th, 7th, 11th, and 13th harmonics at the line side — this avoids the need for a separate harmonic filter in most installations and keeps the total harmonic distortion (THD) low enough to meet IEEE 519 without additional hardware. The drive is assembled in a floor-standing enclosure with separate air flows for the power cells and the transformer section, allowing the forced-convection cooling system to manage the thermal load of 16,600 to 23,200 m³/h of cooling air depending on the efficiency variant.
Overload capability and duty-cycle planning
The ATV1200A8605555 offers two overload profiles: standard overload handles 1.2× rated current for 60 seconds and 1.5× for 3 seconds; high overload handles 1.5× for 60 seconds and 1.85× for 3 seconds. For a 719 kW motor driving a high-inertia load like a centrifuge or a crusher, the high-overload setting gives the extra torque margin during acceleration without oversizing the drive frame. The prospective line short-circuit current withstand is 31.5 kA for 150 ms, which means the drive can ride through a bolted fault on the upstream transformer without internal damage — a critical spec for coordination studies in medium-voltage switchgear. Dielectric strength between earth and power terminals is 20 kV AC, and isolation between power and control circuits is electrical. This allows the control wiring to share a panel with sensitive instrumentation without coupling noise or risking insulation breakdown during a surge.
Physical footprint and site integration
The enclosure dimensions vary by efficiency variant: standard efficiency measures 1400 mm deep × 2860 mm wide × 2590 mm high; high efficiency adds depth to 1500 mm, width to 3460 mm, and height to 2740 mm. The operating position is vertical ±10 degrees, so the drive must sit on a level floor — no wall-mount or side-lay options. Power connections are via M10 screw-type bars accepting up to 6 × 40 mm² cable per phase (/R, /S, L3/T), with entry from the bottom or top. The control supply requires an external 220 V AC source at 3 kVA, and the cooling fan runs on a separate 380 V AC feed — plan for two auxiliary circuits in the MCC bucket.
Standards compliance and approvals
The drive carries CE marking and complies with EN/IEC 60204-11, EN/IEC 60529, EN/IEC 61800-3, EN/IEC 61800-4, and EN/IEC 61800-5-1. Pollution degree 2 per EN/IEC 61800-5-1 and overvoltage category II confirm it is designed for clean, controlled environments — not for outdoor or condensing-humidity installations without additional shelter.