Product Description:

The 175U3339 brake resistor is manufactured by Danfoss and belongs to the VLT Brake Resistors series. Installed on the DC link of a VLT variable frequency drive, it converts regenerative current into heat so the bus voltage stays within safe limits during rapid motor deceleration. This passive component supports repeatable stopping profiles and protects drive semiconductors in material-handling lines, centrifugal pumps, and high-inertia fans that experience frequent braking cycles.

The resistor is cabled with conductors up to 1.5 mm², a size that matches the thermal and current demands of its circuit terminals. Its continuous brake power is rated at 1.400 kW, indicating the amount of energy it can dissipate without exceeding surface temperature limits during prolonged operation. Electrical loading is governed by a resistance of 28 Ω, which controls the instantaneous braking current drawn from the DC bus at a given voltage. A thermal relay set to trip at 6.7 A is integrated for overtemperature protection; it opens the control loop if the resistor reaches its maximum permissible heat level. The housing carries an IP54 rating, providing limited protection against dust ingress and water splashes so the unit can be mounted in ventilated spaces near the drive.

Field wiring uses a wired connection to simplify the parallel installation of multiple brake elements when higher peak absorption is necessary. The steel enclosure measures 400 mm in length, allowing straightforward placement across standard cabinet widths while providing adequate surface area for cooling. The unit is compatible with motors up to 15 kW when operated at 2,800 rpm on a 400 V power supply. This capacity allows the resistor to handle energy produced during full-speed stops under the stated operating conditions. With a mass of 8.2 kg, the assembly adds moderate weight to a drive panel while remaining practical to mount and service.