By WCED

PEN Fault Detection + Surge Protection Device

£77.50 - £146.00
£85.00
£85.00
Recommended With Surge Protection

BS 7671 Amendment 2 risk assessments almost always require surge protection on EV charger circuits — most customers select this option. Shown price includes it.

  • American Express
  • Apple Pay
  • Bancontact
  • Diners Club
  • Discover
  • Google Pay
  • iDEAL Wero
  • Maestro
  • Mastercard
  • Shop Pay
  • Union Pay
  • Visa

Supplied and supported by Eco Harmony — your trusted UK specialist for EV charging and electrical protection.

1-Year Warranty

Fast UK Shipping

Single & Three Phase

IP40 & IP65 Rated

Hugely Customisable

Standard Shipping 3-5 Buisness days£10
Express Shipping 1-2 Buisness days£20
SKU: WPEPME08/SP
Collections:

This single-phase PME consumer unit provides PEN fault detection and 40A RCBO protection as standard, in a weatherproof plastic IP65-rated enclosure. It is designed for EV charger installations on PME (TN-C-S) supplies — including outdoor and exposed mounting locations — where the charger does not include built-in PEN fault detection. Select from optional add-ons — surge protection, kWh metering, and load balancing — to build the exact specification your installation requires.

PEN fault protection is included as standard on every variant. All options of this product include the PEN fault detection module and 40A RCBO. The optional extras let you add surge protection, energy monitoring, and load balancing — choose only what your installation needs. For the indoor metal version of this unit, see the IP40 metal version.
IP65 — suitable for outdoor and exposed mounting. This plastic enclosure is fully dust-tight and protected against water jets, making it suitable for external wall mounting, driveways, car ports, and any exposed outdoor location. If the unit will be installed indoors (garage, utility room) the IP40 metal version is also available.

Why it matters: on a PME (TN-C-S) supply, an open-PEN fault can put mains voltage onto every earthed metal part connected to your installation — including the EV charger casing. BS 7671 Amendment 2 requires protection against this on EV charger circuits. This unit detects the fault and disconnects within 5 seconds, and adds Type 2 surge protection for the charger's electronics — both in one enclosure, no earth rod required.

  • In stock — standard shipping 3–5 business days, express 1–2 business days

Included as standard on every variant

  • PEN fault detection module — monitors supply voltage continuously, disconnects the charger within 5 seconds on fault detection
  • 40A Type A RCBO — combined residual current and overcurrent protection
  • Plastic IP65 weatherproof enclosure — DIN rail mounted, pre-wired, ready to connect

Optional extras — select when ordering

Option What it adds When to choose it
Surge Protection
Optional 		Type 2 SPD — protects charger electronics from transient overvoltages caused by lightning and grid switching Recommended for most installs. BS7671 Amendment 2 risk assessment almost always requires it
kWh Meter
Optional 		Records how much electricity the EV charger uses over time Rental properties, workplace charging, HMRC mileage reimbursement, or any install where usage tracking is needed
Load Balancing
Optional 		Monitors whole-home consumption and automatically reduces charger output to prevent the supply fuse from tripping Where incoming supply capacity is limited or other high-demand appliances (showers, ovens, heat pumps) run alongside the charger

All optional extras can be combined. For example, you can order surge protection + kWh meter + load balancing all in a single unit. Select your required combination when adding to basket.

Technical specifications

Specification Detail
Supply type Single-phase TN-C-S (PME)
PEN fault detection Included as standard — all variants
RCBO rating 40A, Type A
Enclosure type Plastic
Enclosure rating IP65 (outdoor and indoor use)
PEN fault trip threshold <207V or >253V
Disconnect time Within 5 seconds
Surge protection Type 2 SPD — optional add-on
kWh metering Optional add-on
Load balancing Optional add-on
Mounting 35mm DIN rail, wall-mountable
Regulation compliance BS 7671:2018 Amendment 2, Reg 722.411.4.1
Suitable for Single-phase 7kW EV chargers, domestic and outdoor installs

IP65 vs IP40 — which version do you need?

This unit — IP65 Plastic IP40 Metal version
Enclosure Plastic Metal
IP rating IP65 — outdoor and indoor IP40 — indoor only
Suitable for External walls, driveways, exposed locations, garages Garage, utility room, plant room
PEN fault detection Included as standard Included as standard
Optional extras Surge, kWh meter, load balancing Surge, kWh meter, load balancing

Frequently asked questions

Does every variant include PEN fault detection?
Yes. PEN fault detection and the 40A RCBO are included as standard on every option of this product. The optional extras — surge protection, kWh metering, and load balancing — are additions on top. You cannot order this unit without PEN fault detection.
Do I need to add surge protection?
BS 7671 Amendment 2 requires a risk assessment for surge protection on EV charger circuits. In practice, the assessment almost always concludes that Type 2 surge protection is needed — modern EV charger electronics are vulnerable to transient overvoltages from lightning and grid switching. It is strongly recommended for most installs and is already pre-fitted if you select that option.
When would I need a kWh meter?
A kWh meter records how much electricity the EV charger has consumed. Common uses include: rental properties where the landlord wants to recover the cost of electricity from tenants; workplace charging where employees claim HMRC mileage reimbursement; commercial installs requiring per-session energy billing; or any install where usage data is needed.
What does load balancing do and do I need it?
Load balancing monitors the total electricity consumption at the property and automatically reduces the EV charger's output current when overall demand is high — preventing the main supply fuse from tripping. It is particularly useful where the incoming supply is limited (e.g. 60A or 80A single-phase), or where an electric shower, oven, or heat pump may run at the same time as the charger.
What is the difference between this and the IP40 metal version?
The two products are identical in function and available options — both include PEN fault detection as standard and offer the same surge protection, kWh meter, and load balancing extras. The only difference is the enclosure: this unit uses a weatherproof plastic IP65 enclosure suitable for outdoor and exposed mounting, while the IP40 version uses a metal enclosure for indoor use only.
Does this unit remove the need for an earth rod?
Yes. A compliant PEN fault detection device is a recognised alternative to a TT earthing system under BS 7671 Amendment 2. No earth rod or groundworks are required when this unit is installed.

Related products and resources

IP40 Indoor Metal Version 3-Phase PEN Unit Product Finder PME FAQs Understanding PEN Protection
PEN Fault Detection — Standard IP65 Weatherproof Outdoor Use Plastic Enclosure Single-Phase 40A RCBO Optional Surge Optional kWh Meter Optional Load Balancing BS 7671 Compliant No Earth Rod UK Stock
WCED PEN fault detection device in metal enclosure for EV charger PME protection,
£85.00
£85.00

Blog posts

View all