5-1 Standard Specification List Models without a Built-in Resistor (3G3AX-RBU23/-RBU24/-RBU42/- RBU43) 5 Specifications *1. To use the Braking Resistor (3G3AX-RAB/-RBB/-RBC) for the 400-V class Regenerative Braking Unit, be sure to connect two resistors of the same model in series. If the 400-V class Regenerative Braking Unit is operated with a single Braking Resistor, the Braking Resistor may be damaged. *2. Set the DIP switches. 5-3 Voltage class 3-phase 200-V class 3-phase 400-V class Model (3G3AX-) RBU23 RBU24 RBU42*1 RBU43*1 Connectable resistance Continuous operation 6 Ω min. 4 Ω min. 24 Ω min. 12 Ω min.
Short-time operation/ Allowable operation cycle / Allowable continuous ON time 4 Ω min. Cycle 1/5 (2 min ON/ 8 min OFF) 2 min 2 Ω min. Cycle 1/5 (2 min ON/ 8 min OFF) 2 min 10 Ω min. Cycle 1/10 (10 s ON/ 90 s OFF) 10 s 6 Ω min. Cycle 1/5 (2 min ON/ 8 min OFF) 2 min Operating voltage ON/OFF ON: 362.5 ± 5 V, OFF: 355 ± 5 V (−5 % or −10 % setting available) ON: 725 ± 5 V, OFF: 710 ± 5 V (−5 % or −10 % setting available) Operation indication LED ON (Lit) Maximum number of units in parallel operation*2 2 units Protective functions Built-in power module overheat protection Built-in relay specifications • The temperature relay operates if the cooling fin reaches approx. 100°C or more.
• Rating of contact 240 V AC 3 A (R load) 36 V DC 2 A(R load) • Minimum load 5 V DC 50 mA (R load) Operating environment Ambient temperature −10 °C to 50 °C Ambient storage temperature −20 °C to 65 °C (short-time temperature during transport) Humidity 20 % to 90 % (with no condensation) Vibration 4.9 m/s2 (0.5G) 10 to 55 Hz Location At a maximum altitude of 1000m; indoors (without corrosive gases or dust) Paint color Munsell 5Y7/1 (cooling fan: aluminum ground color)