178B2139 by Danfoss

The 178B2139 is a wall-mounted frequency converter produced by Danfoss and belongs to the FCD 300 Micro Drives series. As a decentralized drive, it mounts close to the motor and supplies variable-speed control for small induction motors used on conveyors, mixers, and similar equipment. By modulating output frequency and torque on demand, the unit reduces control-cabinet size and shortens cable runs in distributed industrial automation cells. It is suited to modular machine sections where local speed control is preferred over a centrally mounted drive panel.

This drive accepts a three-phase supply of 3 x 380-480 V, and its inverter section is rated for 0.37 kW of continuous motor power, which corresponds to 0.50 HP. An IP66 housing seals the electronics against high-pressure washdown, while the factory-fitted integral 1A filter limits conducted radio-frequency emissions on the mains leads. Network integration is handled through Profibus DP V0/V1 3 Mbaud, allowing setpoint exchange and diagnostic access from PLCs. Because there is no display, parameter entry is completed with remote software or handheld programmers. The lack of a terminal box means all power, control, and fieldbus conductors land on molded connectors to maintain the enclosure rating, and this arrangement keeps the enclosure closed during normal operation.

The drive is set for a Processing Application profile, and its electronics use a Standard protective coating that withstands moisture and light chemical exposure typical of food or beverage lines. It also includes the Extended (24 V ext.) option, so control logic and fieldbus communication can stay powered from an auxiliary source during mains interruptions. This allows the control system to keep communication active briefly after a supply loss. Auxiliary control power is useful where upstream controls need time to register a fault condition before the unit shuts down.