When upgrading your consumer unit, choosing between RCDs (Residual Current Devices) and RCBOs (Residual Current Breakers with Overcurrent Protection) is crucial for safety and compliance. While both protect against electrical faults, RCBOs offer a much greater level of protection.
In this guide, we’ll cover:
- Key differences between RCDs & RCBOs
- Why RCBOs are the better choice for most installations
- How Fusebox SPD Consumer Units enhance safety
- Top recommended RCBO consumer units
1. RCD vs. RCBO: Key Differences
| Feature | RCD | RCBO |
|---|---|---|
| Protection | Only detects earth leakage (prevents shocks) | Detects BOTH earth leakage & overcurrent (shock + fire prevention) |
| Tripping | Cuts power to multiple circuits (nuisance tripping) | Isolates only the faulty circuit (no whole-board shutdown) |
| Compliance | Meets minimum 18th Edition | Exceeds 18th Edition (best practice) |
| Cost | Cheaper upfront | Slightly higher cost (saves money long-term) |
Why RCBOs Are the Smarter Choice
- No nuisance tripping: If a fault occurs on one circuit (e.g., a faulty appliance), only that circuit shuts off—not your entire property.
- Easier troubleshooting: Electricians can pinpoint faults faster.
- Future-proofing: Mandatory for many commercial/rental properties.
2. What's the Best Solution RCBO or RCD?
For maximum safety and compliance, pair RCBOs with a Fusebox SPD (Surge Protection Device) Consumer Unit.
Key Benefits of Fusebox SPD Units
- Built-in surge protection (mandatory under 2024 regulations)
- Fire-resistant metal enclosure (non-combustible)
- RCBO-compatible (no need for separate RCDs)
- Compact design (saves space in fuse boxes)
3. When Should You Use an RCD Instead?
RCBOs are the best choice for most installations, but RCDs may still be used in:
- Budget retrofits (where RCBOs are cost-prohibitive)
- Non-critical circuits (e.g., garden lighting on a dedicated RCD)
- Warning: Using only RCDs leaves you vulnerable to whole-board tripping.
4. Installation Tips for RCBO Consumer Units
- Always hire a certified electrician (DIY work violates Part P regulations).
- Label circuits clearly (e.g., "Kitchen Sockets – RCBO Protected").
- Test monthly using the built-in RCBO test button.
5. FAQs
Q: Are RCBOs required by law?
A: Not yet mandatory, but strongly recommended under 18th Edition guidelines. SPDs are required for new installations.
Q: How much does an RCBO consumer unit cost?
A: Prices start at around £160 + VAT for a typical 10 way (10 RCBO or 10 Circuit) FuseBox SPD consumer unit
Q: Can I mix RCDs and RCBOs in one unit?
A: Yes (called a "high integrity" board), but all critical circuits such as fire alarms should use RCBOs.
Upgrade to an RCBO consumer unit today:
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