Product Description:

The 178B0756 is an AC variable frequency drive produced by Danfoss within the VLT 6000 HVAC Drives series. Designed for ventilation and hydronic circuits, the unit modulates induction motor speed so building automation systems can match fan or pump output to real-time demand, reducing energy use and mechanical stress. The self-contained drive integrates power conversion, control electronics, and an operator interface for standalone or networked operation in air-handling units, chillers, and cooling tower systems.

It draws a three-phase supply rated at 380–460 VAC, allowing direct connection to common industrial power sources without a step-down transformer. The inverter section provides a continuous output of 37 kW / 50 HP, making it suitable for medium-sized supply and exhaust fans in commercial facilities. A cast-aluminum housing with a compact IP54 enclosure limits dust ingress and protects live parts from splashing water, allowing installation in suitable mechanical rooms without an additional enclosure. Electromagnetic compatibility is supported by an integrated Class A1 and B filter that attenuates conducted emissions on the motor and power leads. For supervisory control or energy management integration, the unit communicates over Profibus DP V1, providing real-time setpoint control, status monitoring, and alarm reporting.

The front panel includes an LCP, providing a removable keypad and graphical display for local parameter access, manual start and stop control, and fault diagnostics. Internally, the drive uses a standard unit configuration without preinstalled optional I/O or application boards. Its controls are configured for HVAC operation, supporting PID airflow regulation, sleep functions, and automatic resonance avoidance for fan and pump applications. The drive contains uncoated circuit boards, so the installation environment must remain within the permitted humidity and contamination limits to prevent moisture, dust, or corrosive substances from affecting the electronics.