178B8578 by Danfoss

The 178B8578 is a low-voltage AC drive produced by Danfoss for the VLT 2800 Low Voltage Drives series. It is installed between the mains and a three-phase induction motor to modulate frequency and voltage in process-oriented machinery such as mixers, conveyors, and dosing pumps. By varying output frequency and voltage, it lets the connected motor match process demand instead of running only at full line speed. This supports smoother control in applications that need gradual acceleration, deceleration, or continuous speed adjustment.

The drive accepts a line supply of 380-480 V ±10% at 50 Hz or 60 Hz, and it is designed for three-phase networks, enabling direct connection to standard industrial switchgear. Its continuous output is rated at 0.75 kW, which corresponds to 1.0 HP. That output level is suitable for small continuous-duty loads where stable motor control is more important than high power. An internal brake transistor is included, providing rapid deceleration when commanded. Because the enclosure is rated IP20, the unit must be installed inside a control cabinet, which also helps prevent accidental contact with live parts. No application option card is fitted, and the RFI filter is omitted, so electromagnetic compliance must be addressed at the panel level.

The Bookstyle housing fits narrow DIN-rail or back-plate arrays while maintaining cooling gaps between adjacent drives. Its slim format helps when several drives are mounted side by side in a shallow enclosure. A protective coating helps shield internal boards from humidity common in processing areas. Setup and monitoring rely on the built-in display that follows the SLCP keypad standard, so basic operation can be handled from the unit itself. Communication expansion is limited by the lack of a fieldbus option, so speed references come from analog inputs or local settings.