3 Phase PME Fault Detection Unit (WARB5100C/PME)
18th Ed. Compliant
2-Year Warranty
UK Stock
Free Delivery £30+
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Pre-wired in the UK and built to order – allow up to 3 working days for dispatch. The WARB5100C/PME is a dedicated 3 Phase PME Fault Detection Unit, designed to safely isolate PME / PEN loss faults without requiring an earth rod. It includes a 100A MCB main switch and...
Pre-wired in the UK and built to order – allow up to 3 working days for dispatch.
The WARB5100C/PME is a dedicated 3 Phase PME Fault Detection Unit, designed to safely isolate PME / PEN loss faults without requiring an earth rod. It includes a 100A MCB main switch and PME relay, giving installers a fast, regulation-compliant solution for EV charging hubs, commercial chargepoints, and other three-phase systems.
The PME relay continuously monitors supply voltages across all three phases (400V / 415V). If undervoltage is detected (below 207V), the board disconnects automatically and resets when stable. If overvoltage is detected (above 253V), it disconnects and requires a manual reset using the built-in red reset button. This ensures safe fault handling and compliance with BS7671:2018+A2:2022.
Installer Tip: This base model provides PME monitoring with a 100A MCB only. For sites requiring surge or RCBO protection, see the other variants in the PME range.
Key Features
- PME Fault Protection: Isolates all poles and earth on PEN loss
- 100A MCB Main Switch: Provides overcurrent isolation for the supply
- Automatic Monitoring: Detects undervoltage & overvoltage across all three phases
- Reset Functions: Auto reset on undervoltage recovery; manual reset for overvoltage
- Compliance: Fully meets BS7671:2018+A2:2022 Amendment 2 requirements
- Application: EV chargers (e.g. Tesla Wall Connector), commercial chargepoints, and 3-phase sites without earth rods
Variant Comparison
| Model | Configuration | Best Use Case |
|---|---|---|
| WARB5100C/PME (This Product) | 100A MCB + PME Relay | Base option for PME fault detection only |
| WARB5100C/PMESP | 100A MCB + PME Relay + SPD | Adds surge protection for EV & solar sites |
| WARB5100C/PME40R | 100A MCB + PME Relay + 40A RCBO | Adds overload & residual protection |
| WARB5100C/PME40RSP | 100A MCB + PME Relay + 40A RCBO + SPD | Full coverage with surge + RCBO protection |
| WARB5100C/PME63DRSP | 100A MCB + PME Relay + 63A RCBO + SPD | Higher load three-phase installs with full protection |
What faults does this protect against?
It detects PME/PEN faults, undervoltage, and overvoltage across all three phases. On detection, it isolates all live and earth conductors to prevent dangerous touch voltages.
Do I still need an earth rod?
No. The PME relay eliminates the need for an earth rod, making installs faster and more cost-effective while remaining compliant.
Which EV chargers is it compatible with?
It supports any three-phase charger — including Tesla Wall Connectors and commercial chargepoints — especially those without built-in PME protection.
What’s included in this model?
This version includes a 100A MCB main switch and PME relay only. For surge or RCBO protection, see other variants in the PME range.
What happens during undervoltage or overvoltage?
If a phase drops below 207V, the board isolates and auto-resets once stable. If a phase exceeds 253V, it isolates and requires manual reset via the red button.
Is this compliant with the 18th Edition?
Yes – fully compliant with BS7671:2018+A2:2022, including PME protection rules.
| Product Code | WARB5100C/PME |
| Rated Voltage | 400V / 415V (3 Phase) |
| Voltage Monitoring Range | 207V – 253V per phase |
| Main Switch | 100A Curve C MCB (5-pole) |
| Surge Protection | Not included (see SP or RSP models) |
| Frequency | 50Hz |
| Ingress Rating | IP40 (indoor use) |
| Reset Functions | Auto reset (undervoltage), Manual reset (overvoltage) |
| Standards | BS EN 61439-3, BS7671:2018+A2:2022 |
| Build Time | 3 working days from order |
This PME fault detection unit is supplied pre-wired, labelled, and ready for connection, but must only be installed by a qualified electrician. All work should comply with the IET Wiring Regulations (BS7671:2018+A2:2022).
- Isolate mains before installation
- Fit with correct gland fittings and torque (2.5Nm)
- Test PME relay before commissioning
- Install indoors in a ventilated space (IP40 rated)
