Power Supply

Its primary functions are:

1. AC to DC Rectification: The vast majority of industrial electromagnetic brakes operate on Direct Current (DC), while most factory and motor power is Alternating Current (AC). The most fundamental job of the brake’s power supply is to act as a rectifier, converting the incoming AC voltage into the DC voltage required by the brake’s coil.
2. Voltage Control and Overexcitation: This is the most crucial performance-enhancing function. To achieve rapid and reliable brake release, especially against powerful springs, a high initial magnetic force is needed. However, maintaining this high force generates excessive heat and wastes energy. A sophisticated power supply solves this with a dual-voltage strategy, often called overexcitation or “forcing”:
   • Forcing Voltage: For a brief, timed period (typically a few hundred milliseconds) upon receiving the signal to release, the power supply delivers a high DC voltage (e.g., 205 VDC) to the brake coil. This creates a powerful magnetic field that quickly overcomes the spring force and snaps the brake open.
   • Holding Voltage: Once the brake is open, the power supply automatically reduces the output to a much lower, continuous “holding” voltage (e.g., 103 VDC). This lower voltage is sufficient to keep the brake disengaged but dramatically reduces power consumption and heat generation in the coil.

The benefits of this controlled power supply are significant:

• Faster Response Time: The high initial voltage results in a much quicker release of the brake.
• Increased Coil Life: By operating at a lower holding voltage, the coil runs significantly cooler, which prevents the breakdown of its insulation and extends its service life.
• Rapid Engagement: When power is cut, the weaker magnetic field of the holding voltage collapses much faster than a full-power field would, allowing the springs to engage the brake more quickly for faster, more precise stops.
• Energy Efficiency: Less power is consumed during operation.