RCD, RCCB and RCBO: Residual Current Protection Explained

Understand the product names

RCD is a broad term for residual current protection. An RCCB provides residual current protection without integral overcurrent protection; an RCBO combines residual current and overcurrent functions. Confirm the product documentation, since catalog terminology and national usage differ. The device must fit the protection design for the complete circuit.

Read both current values

Rated current in amperes and rated residual operating current are different specifications. The first is not a measure of earth-leakage sensitivity. Record both values alongside poles, voltage, frequency and time-delay characteristics. Choosing a device only because its ampere rating matches the old unit can miss an essential protection parameter.

Match waveform detection to the load

Type AC, A, F and B devices have different residual-current detection characteristics. Electronic loads and frequency converters can affect the required type. Follow the equipment manufacturer guidance and project design; do not substitute one type for another based on price. An MCB B trip curve and an RCD Type B refer to different characteristics.

International terminology matters

A product described as an RCD or RCCB must not be assumed equivalent to a US GFCI requirement. Ask for the exact required device standard and certification. For marina and shore-power enquiries, provide the system arrangement and project requirements for the responsible designer to assess.

Prepare the enquiry

Include SKU, quantity, rated current, residual operating current, waveform type, poles, delay, voltage and destination. For replacements, send a clear photograph of every marking. Ask for manufacturer documentation before accepting a different series.

Explore catalog references

Examples for product research; suitability and availability must be confirmed for your project.

• Schneider Electric A9D34620 — Residual current breaker with overcurrent protection (RCBO), Acti9 iDPNa Vigi, 1P+N, 20A, C curve, 4500A, AC type, 30mA
• Schneider Electric A9DE3716 — Residual current breaker with overcurrent protection (RCBO), Acti9 iCV40N, 3P+N, 16A, C curve, 6000A, AC type, 30mA
• Schneider Electric A9D31632 — Acti 9 iDPN N Vigi - RCBO - 1P+N - 32A - C Curve - 6000A - 30mA - type AC

Manufacturer references

• Schneider Electric documentation: A9D34620
• Schneider Electric documentation: A9DE3716
• Schneider Electric documentation: A9D31632
• Schneider Electric Electrical Installation Guide

These AI-assisted purchasing guides use manufacturer references and catalog data. They are not installation instructions or a substitute for project-specific engineering approval.