Product Description:

The RZK01.1-132-NN is a resistive braking and cooling module produced by Bosch Rexroth Indramat within the RZK Heat Exchangers series. It is installed alongside drive controllers to absorb regenerative energy, convert it into thermal output, and move that heat away from control cabinets. By providing a dedicated thermal path, the unit helps protect power sections from overvoltage events during rapid deceleration or load reversals in automated machinery.

Electrical absorption starts with a resistance of 2.2 Ω, a low value chosen to allow substantial current flow without exceeding component limits. Under continuous duty, the resistor is rated for 2 kW of braking power, so drives that routinely cycle can discharge energy at this level indefinitely. For emergency stops, it accepts a peak load of 270 kW for a brief 0.1 s, preventing DC-bus voltage rise when inertia is high. Heat transfer through the fin package is supported by a cooling capacity of 4 kW, indicating how much thermal energy the exchanger can move to the surrounding air before temperature equilibrium is reached. These values indicate how the device matches servo axes with different inertia profiles and duty cycles.

During operation, surface temperature and mounting clearance must be considered. The outer surface may climb to 80 °C during peak operation, so wiring and nearby components must tolerate that exposure. Installation requires at least 200 mm of clearance above the housing to maintain natural convection paths. The enclosure carries an IP20 protection class, meaning finger-safe openings but no sealing against liquids, which suits placement inside control enclosures. Thermal mass and geometry yield a response lag of 13.6 s, giving drives time to spread successive braking pulses without overshooting the resistor’s rating. At 16 kg, the module adds moderate weight to a panel, so mounting rails must be sized accordingly.