178B1656 by Danfoss

The 178B1656 is a decentralized AC variable-frequency drive built by Danfoss as part of the FCD 300 Micro Drives series. By combining the inverter, control electronics, and wiring compartment in one compact body, the unit mounts directly on processing equipment. It regulates three-phase induction motors so conveyor belts, mixers, and agitators can run at the exact speed required by each industrial automation step. This placement shortens motor leads and helps reduce electromagnetic noise inside plant cabinets.

The drive accepts a three-phase utility supply of 3x380-480 V, a range that matches common industrial networks. Within that range, it can deliver a continuous electrical output of 0.55 kW, which corresponds to a mechanical shaft rating of 0.75 HP for modest-duty machines. A die-cast enclosure certified to IP66 blocks dust ingress and withstands high-pressure washdown, letting the unit sit on machinery frames in sanitary zones. Adjustments can be made through a front-mounted display connector that accepts the Danfoss remote keypad. The housing also includes a gasketed conduit plate so power and control cables can enter without compromising the seal.

A factory-applied standard coating on the internal boards adds chemical resistance in installations that use cleaning agents. Conducted emissions are suppressed by the integral 1 A RFI filter, which removes the need for a separate EMC filter in the supply line. All conductors terminate in a rear box that uses wall-mounted terminals with metric threads, simplifying installation alongside European conduit systems. Communication is limited to hard-wired I/O because the device ships without fieldbus capability, matching the standard configuration. The unit is intended for applications that need a compact drive mounted close to the load rather than in a control cabinet.