178B3228 by Danfoss

The 178B3228 is an AC variable frequency drive manufactured by Danfoss and assigned to the VLT 2800 Low Voltage Drives series. The unit functions as a speed regulator for small industrial pumps, fans, and conveyors, translating low-voltage mains power into a controlled output frequency suitable for asynchronous motors. Its book-style housing and integrated interface let panel builders fit the drive into narrow cabinets while still accessing parameters from the built-in display.

This drive draws power from a single-phase supply rated at 200-240 V AC, delivering a mechanical output of 3.0 HP that corresponds to an electrical rating of 2.2 kW. The housing carries an IP20 ingress rating, so installation inside a protected enclosure is recommended. Communication with higher-level controllers is available through Profibus DP (12 Mbaud), and local adjustments are made using the built-in display (SLCP). The compact book-style form factor measures 75 mm in width, 200 mm in height, and 168 mm in depth, which helps conserve cabinet space without external heatsinks. An internal RFI filter limits conducted emissions toward adjacent equipment.

During steady operation, the converter draws an apparent power of 1.3 kVA, a figure used when sizing upstream circuit protection. The integrated filter meets EN 55011 Class A1 emission limits, enabling compliance in industrial environments that share sensitive instrumentation. Because the input stage is single-phase, only two mains conductors and a protective earth are required, which simplifies wiring in retrofit panels. The unit synchronizes its output modulation with incoming mains at 50/60 Hz, so no adjustment is needed when equipment is relocated between regions. The book-style enclosure helps the unit fit densely packed low-voltage cabinets with limited clearance.