How long should a capacitor be allowed to discharge before grounding?

A capacitor should typically be allowed to discharge for at least 5 minutes before it is grounded. This duration is important for ensuring safety, as capacitors can retain a charge even after power is removed from a circuit. The discharging process helps to minimize the risk of electric shock or damage to equipment when handling the capacitor.

Grounding a capacitor too soon can pose hazards since a residual charge may still exist. Allowing a longer discharge time, such as 5 minutes, helps to ensure that the voltage across the capacitor has dropped to a safe level. Additionally, depending on the capacitor type and its capacitance, longer discharge times might be justified. As a general rule of thumb in electrical work, following the recommended wait time before grounding maximizes safety practices in handling stored electrical energy.