Product Description:

The MPS45B is a DC power supply unit produced by Okuma within the MPS Power Supplies series. Designed for CNC and general automation cabinets, this unit converts incoming three-phase AC power into a regulated DC bus that feeds spindle inverters and axis servo amplifiers. By supplying a common DC link, the module reduces total wiring and allows regenerative energy from decelerating axes to be redistributed or returned to the grid. This role places the MPS45B at the core of multi-axis machining centers and automated cells.

Its logic circuits receive a control voltage of 24 VDC, isolating signal electronics from the high-energy sections. The main rectifier and filter produce a DC link of 300 VDC, a level matched to the input stage of compatible drive amplifiers for fast torque response. When demanded output power climbs, the supply can support motors totaling 60 hp while remaining within thermal limits. The unit accepts a mains line of 200 VAC, a standard value for Japanese and many North American factory feeders, and internal airflow is provided by a designated UP80B22 cooling fan that directs forced air across the heat sinks and semiconductor bridge.

The available capacity is rated at 45 kW, so machine builders can size multiple spindle or axis converters without exceeding the supply’s continuous power range. Okuma designates the intended load category as Spindle & Axis Drives, indicating use with spindle and axis drive systems that can return braking energy during operation. As a Second Generation module, it supports later drive models while preserving cabinet dimensions from earlier releases. Excess kinetic energy is processed by a power regeneration type circuit that directs returned current to the facility supply instead of burning it in resistor banks, which helps reduce cabinet heat.