What is the difference between high-voltage (DC 90V) and low-voltage (DC 60V) electromagnetic chucks?

For chucks with the same size and design, the power used (in watts) is the same. The difference is that low-voltage chucks need more current and have higher inductance. Because of this, when the magnet turns on, the magnetic force builds up faster, so it can hold the workpiece a bit better at the start.