A modular enclosure may include a number of components, such as floor panels, wall panels and roof panels, which may be interconnected to form a structure such as a shed. Each of the sections consists of a combinat of a spiral coil having a variable coil pitch arranged in a saddle shape configuration. A detection circuit measures an insulation resistance value on the output side of the voltage conversion circuit. These beads can be bonded directly on the flat surface of a flexible backing or bonded onto raised island surfaces.