In most cases, one side of a capacitor is grounded. However, it is not true that this is the case in all designs. The only guaranteed safe way to discharge a capacitor is through a suitable resistor across its terminals.
Grounding either pin of a capacitor to frame ground does not necessarily cause a discharge. In fact, it may apply power to some circuit that does not expect it, potentially damaging it.
Equipment and Safety Grounding Equipment grounding is a safety measure to prevent electric shock. It provides a low-resistance path for fault currents to flow into the ground in case of a fault or equipment failure, minimizing the risk of electric shock to individuals who come in contact with the equipment.
Static Grounding: Static grounding is a method that removes charged static electricity between the earth and an object, which is an imbalance in electrical charge between two objects. Static grounding protects equipment from damage and is necessary for facilities operating in hazardous areas.
Conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected to earth so as to limit the voltage to ground on these materials. Where the electrical system is required to be grounded, these materials shall be connected together and to the supply system grounded conductor.
The grounding wire provides a direct path to the ground, and as a result, electricity is safely discharged. In an electric circuit, an active or "hot" wire supplies power, while a neutral wire is a return path. A grounding wire provides a safe path for electrical current to return to the ground in the event of a short circuit.