Abstract: A modular device that can operate as an electrical generator. First and second coil support plates are arranged in parallel orientation relative to each other forming a gap between the first and second coil support plates. Removable C-cores, each having wire coils, are removably attached to the first and second coil support plates. A rotor disc having selectively arranged magnets is disposed in the gap between the first and second coil support plates and is permitted to rotate about an axis that is perpendicular to the rotor disc and the parallel first and second coil support plates; a drive motor can power rotation of the rotor disc. As the disc rotates, electrical current is generated. The C-core assemblies can be interchanged, checked, removed and/or replaced while the electrical generator remains in operation without requiring cessation of such operation.