vuotovirtasuojakytkimet

Vuotovirtasuojakytkimet, often abbreviated as RCDs (Residual Current Devices), are safety devices designed to protect against electric shock. They function by monitoring the balance of electrical current flowing through a circuit. In a normal circuit, the current flowing out to a device should be equal to the current returning from it. If there is an imbalance, it indicates that some current is leaking out, potentially through a person to ground.

When an RCD detects such a leakage current above a predetermined threshold, it rapidly interrupts the power supply. This "tripping" action significantly reduces the risk of severe electric shock or electrocution. They are commonly installed in homes and workplaces to protect circuits where the risk of contact with live conductors is higher, such as in bathrooms, kitchens, and outdoor areas.

RCDs are not a substitute for earthing, but rather an additional layer of safety. They are particularly effective in situations where the fault current might not be large enough to trip a standard circuit breaker but is still dangerous to a human. Different types of RCDs exist, varying in sensitivity and the type of current they are designed to detect, such as alternating current (AC) or direct current (DC) leakage. Regular testing of RCDs is recommended to ensure their continued proper operation.