WCED Product Datasheets – Technical Information for Installers

Technical datasheets for the complete WCED range — EV circuit protection units, distribution boards, enclosures, and modules. Each entry follows the same structure: product overview, specification FAQs, images, part codes, and a datasheet download. All products comply with BS EN 61439-3 and BS 7671 (18th Edition).

A-Type EV RCBO Kit

Plastic 2–3 way enclosure with A-type RCBO · WMEV / WME series

The WMEV range provides earth leakage and overload protection for single EV charger installations on PME supplies. Each unit ships ready to install — the A-type RCBO detects AC and pulsating DC earth leakage up to 6mA and offers overload protection in a single compact device. The twin-handle design makes fault diagnosis straightforward on site: the black handle governs MCB function; the white handle governs RCD function. If only the black handle trips, the fault is an overload or short circuit. If both handles trip together, a residual current fault has been detected.

What earth leakage types does the A-type RCBO detect?
The A-type RCBO detects Type AC (sinusoidal alternating current) and pulsating DC earth leakage up to 6mA. This covers the leakage profiles of the majority of Mode 3 EV chargers and makes an earth rod unnecessary on PME-supplied installations where this unit is fitted.
What does the twin-handle system indicate about the fault type?
The black handle controls the MCB (overload/short-circuit) function and the white handle controls the RCD (earth leakage) function. If only the black handle trips, the fault is overload or short circuit. If both handles trip simultaneously, the fault is a residual current (earth leakage) event. This removes the guesswork during fault-finding and speeds up site diagnosis.
Are B-curve and C-curve variants both available?
Yes. Both B-curve (general domestic/light commercial) and C-curve (higher inrush applications) are available across 6A, 10A, 16A, 20A, 25A, 32A, and 40A ratings. The 3-way enclosure options also include a combined RCBO + MCB configuration for dual-circuit protection.
What is the enclosure IP rating?
The standard WMEV enclosures are suitable for indoor or sheltered installations. For outdoor or exposed locations, the WPRC (plastic IP65) or WMIP (metal IP65) ranges should be selected instead.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WMEV206B 2-module enclosure, 6A B-curve RCBO 74×175×90
WMEV210B 2-module enclosure, 10A B-curve RCBO 74×175×90
WMEV216B 2-module enclosure, 16A B-curve RCBO 74×175×90
WMEV220B 2-module enclosure, 20A B-curve RCBO 74×175×90
WMEV225B 2-module enclosure, 25A B-curve RCBO 74×175×90
WMEV232B 2-module enclosure, 32A B-curve RCBO 74×175×90
WMEV240B 2-module enclosure, 40A B-curve RCBO 74×175×90
WMEV206C 2-module enclosure, 6A C-curve RCBO 74×175×90
WMEV210C 2-module enclosure, 10A C-curve RCBO 74×175×90
WMEV216C 2-module enclosure, 16A C-curve RCBO 74×175×90
WMEV220C 2-module enclosure, 20A C-curve RCBO 74×175×90
WMEV225C 2-module enclosure, 25A C-curve RCBO 74×175×90
WMEV232C 2-module enclosure, 32A C-curve RCBO 74×175×90
WMEV240C 2-module enclosure, 40A C-curve RCBO 74×175×90
WME323B-32 3-way enclosure, 32B RCBO + 32A MCB 110×175×90
WME32C-32 3-way enclosure, 32C RCBO + 32A MCB 110×175×90
WMEV332B 3-way enclosure, 32A B-curve RCBO + blank 110×175×90
WMEV332C 3-way enclosure, 32A C-curve RCBO + blank 110×175×90
WMEV340B 3-way enclosure, 40A B-curve RCBO + blank 110×175×90
Download datasheet (PDF)

Metal EV Protection Unit with Surge Protection

A-type RCBO + Type 2 SPD · WMRC series · 110×175×91mm

The WMRC range combines an A-type RCBO with a Type 2 surge protection device (SPD) inside a white polyester powder-coated metal enclosure. Multiple circular cable knock-outs (25mm and 32mm) on the top and bottom simplify cable routing. The twin-handle RCBO allows instant fault-type identification: overload or short-circuit if only the black handle trips; residual current fault if both handles trip together. The metal construction provides additional mechanical protection compared to plastic alternatives, making it well-suited for garages, outbuildings, and light commercial EV charging installations.

Why combine an RCBO with surge protection in one enclosure?
Fitting surge protection at the point of EV charger connection protects the charger's electronics from voltage transients caused by lightning strikes, grid switching events, and nearby inductive loads. Combining the SPD with the RCBO in a single enclosure saves DIN rail space, simplifies installation, and reduces the number of separate products to specify and stock.
What surge protection level does the SPD provide?
The WMRC units include a Type 2 SPD rated at 20kA/40kA surge current. Type 2 SPDs are designed for installation at the distribution board or point-of-use, providing protection against indirect lightning strikes and switching transients in accordance with BS EN 61643-11 and the requirements of BS 7671 Amendment 2.
Is the WMRC suitable for outdoor installation?
The WMRC enclosure is metal with powder-coat finish but does not carry a specific IP65 weatherproof rating. For fully exposed outdoor locations, the WMIP (metal IP65) range is the correct choice. The WMRC is suited to covered outdoor areas such as carports, garages, and outbuildings where it will not be subject to direct rain ingress.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WMRC32BSP 4-way metal, A-type 32A B-curve RCBO + SPD 110×175×91
WMRC32CSP 4-way metal, A-type 32A C-curve RCBO + SPD 110×175×91
WMRC40BSP 4-way metal, A-type 40A B-curve RCBO + SPD 110×175×91
WMRC40CSP 4-way metal, A-type 40A C-curve RCBO + SPD 110×175×91
Download datasheet (PDF)
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Plastic Weatherproof EV Protection Unit

IP65 A-type RCBO + Type 2 SPD · WPRC series · 140×205×95mm

The WPRC enclosures are rated IP65 — fully dustproof and protected against water jets — making them the standard choice for outdoor EV charger installations in the UK. Each unit ships pre-fitted with an A-type RCBO (detecting AC and pulsating DC earth leakage up to 6mA) and a Type 2 SPD. The twin-handle RCBO makes fault identification straightforward without test equipment: black handle only = overload/short circuit; both handles = residual current fault.

Does IP65 meet the requirements for an outdoor domestic EV charger installation?
Yes. IP65 is the minimum recommended ingress protection for electrical equipment installed in an exposed outdoor location in the UK under BS 7671. The WPRC range meets this requirement and is suitable for mounting on an external wall adjacent to a driveway, carport, or car park.
What cable entry options are available on the WPRC enclosure?
The WPRC enclosure includes circular knock-outs on the top and bottom panels. These accept standard M20 cable glands, which can be enlarged to M32 on site. Maintaining the IP65 rating requires appropriate cable glands to be fitted once cables are routed.
Can the WPRC be used with three-phase EV chargers?
The WPRC range is a single-phase product. For three-phase EV charger installations (11kW–22kW), the WMTP or WTPN distribution board ranges should be specified instead.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WPRC32BSP IP65 A-type 32A B-curve RCBO + SPD 140×205×95
WPRC32CSP IP65 A-type 32A C-curve RCBO + SPD 140×205×95
WPRC40BSP IP65 A-type 40A B-curve RCBO + SPD 140×205×95
WPRC40CSP IP65 A-type 40A C-curve RCBO + SPD 140×205×95
Download datasheet (PDF)
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Metal Weatherproof IP65 EV Protection Unit

IP65 aluminium enclosure, A-type RCBO + Type 2 SPD · WMIP series · 164×232×102mm

The WMIP range uses a non-combustible aluminium enclosure — inherently resistant to rust, corrosion, and fire — with an IP65 weatherproof rating for fully exposed outdoor installations. A lockable design accepts a standard padlock for added security. The raised DIN rail improves cable routing inside the enclosure and the large wiring space makes installation straightforward. M20 knock-outs can be enlarged to M32 on site. Compliant with BS 7671 (18th Edition) and BS EN 61439-3.

Why choose metal (WMIP) over plastic (WPRC) for outdoor installations?
Both are IP65-rated, but the WMIP aluminium enclosure offers superior mechanical impact resistance, is non-combustible, and is better suited to high-traffic locations such as commercial car parks or industrial sites where physical damage or fire risk is a concern. The aluminium also dissipates heat more effectively in high-ambient-temperature environments.
What is the recommended torque for terminal connections?
The WMIP datasheet specifies a recommended torque of 2.5Nm for all terminal connections. Over-torquing can damage terminals and compromise the connection; under-torquing can cause resistance heating. A calibrated torque screwdriver should be used during installation.
Is the WMIP5 enclosure available without pre-fitted protection devices?
Yes. The WMIP5 (grey) and WMIP5-W (white) are supplied as empty 5-module IP65 enclosures without any pre-fitted devices, allowing the installer to populate them with their choice of WCED protection devices or other 17.5mm DIN rail modules.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WMIP5 5-module IP65 grey metal enclosure (empty) 164×232×102
WMIP5-W 5-module IP65 white metal enclosure (empty) 164×232×102
WMIP32BSP 32A B-curve RCBO + SPD 164×232×102
WMIP32CSP 32A C-curve RCBO + SPD 164×232×102
WMIP40BSP 40A B-curve RCBO + SPD 164×232×102
WMIP40CSP 40A C-curve RCBO + SPD 164×232×102
Download datasheet (PDF)

Weatherproof IP65 B-Type EV Kit

IP65 B-type RCD + MCB · WPEVKIT series · 140×205×95mm

The WPEVKIT63 is specified where the EV charger itself does not include DC leakage protection — for example, older or non-A-type EV charge points. The B-type RCD detects and responds to AC, pulsating DC, and smooth DC earth leakage, providing the most comprehensive leakage protection available for Mode 3 EV charging. The MCB provides overload protection. Housed in an IP65 weatherproof enclosure for outdoor installation.

When should a B-type RCD be used instead of an A-type RCBO?
A B-type RCD is required when the EV charger does not incorporate its own 6mA DC smooth leakage protection. B-type devices detect AC, pulsating DC, and smooth DC earth fault currents — covering all leakage types. An A-type RCBO only covers AC and pulsating DC. If in doubt, check the charger manufacturer's documentation; if it specifies no integral DC leakage protection, specify a B-type RCD.
Can the WPEVKIT63 be used with both 7kW and 22kW chargers?
The WPEVKIT63 includes a 63A B-type RCD and a 40A C-curve MCB, making it suitable for single-phase 7kW charger installations. For three-phase 11kW or 22kW installations, a three-phase solution such as the WMTP or WTPN range is required.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WPEVKIT63-EC IP65 B-type 63A RCD + 40A C-curve MCB 140×205×95
Download datasheet (PDF)

EV Kit — Metal Enclosure

B-type RCD + MCB · WEVKIT series · 110×175×91mm

The WEVKIT63 is the indoor metal equivalent of the WPEVKIT63 — a B-type RCD combined with a C-curve MCB in a compact metal enclosure. Suitable for installations where the EV charger has no integral DC leakage protection and the enclosure can be located in a sheltered indoor or semi-exposed position. The B-type RCD provides full AC, pulsating DC, and smooth DC earth leakage protection.

What is the difference between WEVKIT63 and WPEVKIT63-EC?
Both contain a 63A B-type RCD and a 40A C-curve MCB with the same protection function. The key difference is the enclosure: WEVKIT63 is a metal enclosure without a specific IP65 weatherproof rating, suited to indoor or sheltered installations. WPEVKIT63-EC is a plastic IP65 enclosure designed for fully exposed outdoor locations.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WEVKIT63 B-type 63A RCD + 40A C-curve MCB 110×175×91
Download datasheet (PDF)

EV Connection Units

100A main switch + MCB isolation units · WEVCU / WERM / WSRC series · 110×175×91mm

EV connection units provide isolation and overload protection for EV sockets without a built-in isolator. The 100A main switch provides safe isolation of the charger circuit for servicing or in an emergency. The MCB provides overload and short-circuit protection. WSRC variants add kWh metering for energy monitoring. SPD variants (WEVCU32BSP, WSRC532BSP) include Type 2 surge protection. WPEVCU32BSP is the IP65 weatherproof version for outdoor socket installations.

Why is a 100A main switch specified rather than a lower rating?
The 100A main switch is rated for the isolation function only, not continuous load carrying at 100A. Using a higher-rated switch ensures it can handle the inrush current of EV charger contactors without premature wear, and provides headroom if multiple circuits are eventually connected through the same isolation point.
Can other MCB ratings be fitted instead of 32A?
Yes. The standard catalogue includes 32A and 40A MCB ratings. Other ratings are available to order — contact us with your specific requirement.
Does the WSRC532BSP include kWh metering?
Yes. The WSRC532BSP includes a 100A main switch, 32A B-curve MCB, Type 2 SPD, and a kWh meter — making it the most complete single-enclosure solution for a metered, surge-protected EV socket connection point.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WEVCU 100A main switch + 32A MCB 110×175×91
WEVCU32B 100A main switch + 32A B-curve MCB 110×175×91
WEVCU40B 100A main switch + 40A B-curve MCB 110×175×91
WERM6332 63A A-type RCD + 32A MCB 110×175×91
WEVCU32BSP 100A main switch + 32A B MCB + SPD 175×110×91
WSRC532BSP 100A main switch + 32A B MCB + SPD + kWh meter 175×110×91
WPEVCU32BSP 100A main switch + 32A B MCB + SPD — IP65 8-way enclosure 212×205×95
Download datasheet (PDF)

WTPN 125A Three-Phase Distribution Board

TP&N distribution board with 125A 4-pole main switch + Type 2 SPD · WTPN series

The WTPN range is a robust 1.2mm steel three-phase distribution board for commercial, industrial, and high-demand domestic EV charging installations. Each board is supplied with a 125A 4-pole main switch and a Type 2 surge protection device (SPD) as standard. Solid copper busbar construction ensures low impedance connections. Backed-out terminal screws, keyway mounting points, and separate metal gland plates simplify installation and inspection. Extension boards (WTPNEB14) and spreader boxes (WTPNSB) allow the system to be expanded without replacing the primary enclosure.

What DIN rail devices are compatible with the WTPN board?
The WTPN board accepts all standard WCED 6kA DIN rail devices — including 3-pole MCBs, 4-pole RCBOs, and surge protection modules — without modification or additional hardware. Standard 17.5mm pitch DIN rail accessories from other manufacturers may also be fitted subject to physical compatibility.
Can the WTPN be used for a multi-bay EV charging installation?
Yes. The WTPN is the standard solution for multi-bay EV charging where multiple single-phase or three-phase chargers are fed from a single incoming three-phase supply. A 12-way or 16-way board, for example, provides enough ways for six or eight dedicated 7kW charger circuits, each individually protected by a 3-pole MCB or RCBO.
Is a TPN to single-phase converter kit available?
Yes. Single-phase converter kits are available as accessories, allowing a TPN board to feed single-phase loads from individual phases. See the accessories section for details.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WTPN04-125 4-way TP&N board, 125A 4-pole main switch + Type 2 SPD + 3P 32A MCB 460×505×120
WTPN06-125 6-way TP&N board 460×559×120
WTPN08-125 8-way TP&N board 460×613×120
WTPN12-125 12-way TP&N board 460×613×120
WTPN16-125 16-way TP&N board 460×829×120
WTPN24-125 24-way TP&N board 460×1045×120
WTPNEB14 TPN extension board, 14 modules 460×341×120
WTPNSB TPN spreader box 460×433×97
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A-Type RCBO — DIN Rail

10kA single-module A-type RCBO · WRT series · 17.8×116×76mm

The WRT range are single-module 10kA A-type RCBOs for installation in consumer units, distribution boards, or the WMIP5/WMIP5-W enclosures. They detect AC and pulsating DC earth leakage (30mA sensitivity) and provide overload and short-circuit protection in a single 17.5mm DIN rail module. The bidirectional design makes them suitable for solar PV and other generation installations as well as standard load circuits.

Are these RCBOs suitable for use in solar PV installations?
Yes. The WRT series are bidirectional — they function correctly regardless of the direction of current flow. This makes them suitable for circuits connected to solar PV inverters and battery storage systems where reverse current flow can occur during export periods.
What breaking capacity do the WRT RCBOs offer?
The WRT range is rated at 10kA breaking capacity, which covers the vast majority of domestic and light commercial installations in the UK. For sites with a prospective short-circuit current higher than 10kA, a higher-rated device should be specified.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WRT106B-030 A-type 6A B-curve, high immunity, 30mA 17.8×116×76
WRT110B-030 A-type 10A B-curve, high immunity, 30mA 17.8×116×76
WRT116B-030 A-type 16A B-curve, high immunity, 30mA 17.8×116×76
WRT120B-030 A-type 20A B-curve, high immunity, 30mA 17.8×116×76
WRT132B-030 A-type 32A B-curve, high immunity, 30mA 17.8×116×76
WRT140B-030 A-type 40A B-curve, high immunity, 30mA 17.8×116×76
WRT106C-030 A-type 6A C-curve, high immunity, 30mA 17.8×116×76
WRT110C-030 A-type 10A C-curve, high immunity, 30mA 17.8×116×76
WRT116C-030 A-type 16A C-curve, high immunity, 30mA 17.8×116×76
WRT120C-030 A-type 20A C-curve, high immunity, 30mA 17.8×116×76
WRT132C-030 A-type 32A C-curve, high immunity, 30mA 17.8×116×76
WRT140C-030 A-type 40A C-curve, high immunity, 30mA 17.8×116×76
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Three-Phase SPD Units

8-way IP40 metal enclosure, 4-pole Type 2 SPD + 4-pole MCB or RCBO · WMCUSP4 / WRCUSP4 series

The WMCUSP4 and WRCUSP4 units provide three-phase surge protection at the point of connection for commercial EV chargers and other three-phase loads. Each consists of an 8-way IP40 metal enclosure with a 4-pole 20kA/40kA Type 2 surge protector. The WMCUSP4 includes a 4-pole 10kA MCB; the WRCUSP4 replaces this with a 4-pole A-type RCBO for installations also requiring three-phase earth leakage protection.

What is the difference between WMCUSP4 and WRCUSP4?
Both are 8-way IP40 metal enclosures with a 4-pole Type 2 SPD. The WMCUSP4 includes a 4-pole MCB (overload and short-circuit protection only). The WRCUSP4 includes a 4-pole A-type RCBO, adding earth leakage protection — suitable for installations where the EV charger or equipment being protected does not include integral RCD protection.
At what point in the installation should the SPD unit be fitted?
Type 2 SPDs should be fitted at or as close as possible to the equipment being protected — in this case, at the distribution board feeding the EV chargers or at the EV charger enclosure itself. Installing the SPD upstream at the main incomer only (Type 1 position) provides insufficient protection for sensitive charger electronics at the end of long cable runs.

Part codes

Part code Description
WMCUSP4*** 8-way IP40 metal, 4-pole Type 2 SPD + 4-pole MCB (*** = amperage and curve)
WRCUSP4*** 8-way IP40 metal, 4-pole Type 2 SPD + 4-pole A-type RCBO (*** = amperage and curve)
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PME Fault Detection Units

Three-phase PME relay with automatic isolation · WARB / WMTP series

The WARB and WMTP units automatically monitor supply voltage on 400V and 415V three-phase supplies without manual dip-switch configuration. In the event of a PEN conductor fault — indicated by an under-voltage below 207V or an over-voltage above 253V on any phase — the unit disconnects live, neutral, and earth within 5 seconds, preventing dangerous touch voltages from appearing on exposed metalwork connected to the EV charger. Under-voltage conditions reset automatically when normal voltage is restored; over-voltage conditions require a manual reset (press the red WP9 button) as an additional safety check. The WMTP multi-point versions accommodate two or three RCBO-protected EV charger circuits within a single enclosure.

Does fitting a PME protection unit mean I no longer need an earth rod?
Yes, in most cases. The PME relay disconnects all conductors including the combined neutral/earth (PEN) in the event of a PEN fault, preventing dangerous touch voltages. This eliminates the primary risk that makes an earth rod necessary on PME-supplied EV charger installations under BS 7671 Regulation 722.411.4.1. Always confirm the specific installation meets all relevant requirements before omitting an earth rod.
Does the unit work on both 400V and 415V supplies?
Yes. The WARB and WMTP units automatically detect and adapt to 400V and 415V three-phase supplies with no manual configuration required. The voltage thresholds (under-voltage below 207V, over-voltage above 253V per phase) apply to both supply voltages.
Why does an over-voltage trip require a manual reset but an under-voltage resets automatically?
An over-voltage event (above 253V per phase) may indicate a serious supply fault such as a broken neutral causing voltage imbalance — a potentially dangerous condition that warrants inspection before re-energising. An under-voltage event (below 207V) is more commonly caused by a temporary supply dip or fault that self-clears, so automatic reset is acceptable once normal voltage is confirmed restored.
What is the WMTP multi-point unit and when is it used?
The WMTP28 and WMTP36 are enclosures that combine a PME relay with two or three individually protected RCBO circuits respectively — suitable for small multi-bay EV charging installations where each charger needs its own RCBO protection but a single PME relay monitors the supply for all of them. This reduces panel space and wiring compared to fitting separate units.
Is this product compliant with Amendment 2 of BS 7671?
Yes. The WARB and WMTP PME fault detection units are designed to meet the requirements of BS 7671:2018+A2:2022 Regulation 722.411.4.1, which requires disconnection of all live conductors including the PEN conductor in the event of a PEN fault on PME-supplied EV charger installations.

Part codes & dimensions

Part code Description Dimensions W×H×D (mm)
WARB5100C/PME 100A MCB + PME relay —
WARB5100C/PMESP 100A MCB + PME relay + SPD —
WARB5100C/PME40R 100A MCB + PME relay + 40A RCBO —
WARB5100C/PME40RSP 100A MCB + PME relay + 40A RCBO + SPD —
WMTP28-R40CSP 2× RCBO + 1× PME detector 500×304×112
WMTP36-R40CSP 3× RCBO + 2× PME detector 500×530×112
Download datasheet (PDF)
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Three-Phase Weatherproof Fused Switch

IP weatherproof 3-phase isolation switch · WTFS series

The WTFS range provides three-phase isolation and fused protection in a single weatherproof enclosure, suitable for outdoor disconnection of three-phase EV chargers, heat pumps, and other three-phase equipment. Available in 32A, 63A, 80A, and 100A ratings to suit a range of three-phase load currents.

Is the WTFS suitable for use as a means of isolation for a 22kW EV charger?
A 22kW three-phase EV charger draws approximately 32A per phase at full load. The WTFS32 (32A) is the minimum rated unit suitable, and many installers prefer to specify the WTFS63 to provide headroom. Always verify the charger's maximum continuous current and any de-rating requirements for the installation environment.

Part codes

Part code Description
WTFS32 32A 3-phase weatherproof fused switch
WTFS63 63A 3-phase weatherproof fused switch
WTFS80 80A 3-phase weatherproof fused switch
WTFS100 100A 3-phase weatherproof fused switch
Download datasheet (PDF)

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Frequently asked questions — WCED electrical protection

What is PME protection, and why do I need it for EV charger installations?
PME (Protective Multiple Earthing) is the most common earthing arrangement in the UK, where the neutral and earth conductors are combined in a single PEN conductor upstream and separated only at the consumer's installation. If the PEN conductor breaks, exposed metalwork connected to the earth terminal of the installation — including EV charger enclosures and vehicle bodywork — can rise to a dangerous voltage. A PME fault detection device monitors supply voltages and disconnects all conductors (including the PEN) automatically within 5 seconds of detecting the fault, preventing this hazard.
Do all EV charger installations on a PME supply require PME protection?
BS 7671:2018+A2:2022 Regulation 722.411.4.1 requires that, on a PME supply, the earthing of an EV charging point outside a building must either (a) be via a dedicated earth electrode independent of the PEN conductor, or (b) use an automatic disconnection device that isolates all conductors including the PEN in the event of a fault. The WCED PME relay units satisfy option (b), removing the need for an earth rod in most cases.
What is the difference between A-type and B-type RCD/RCBO protection?
AC-type RCDs detect only sinusoidal alternating current faults — unsuitable for EV charging. A-type devices also detect pulsating DC leakage, covering the majority of Mode 3 EV chargers. B-type devices additionally detect smooth DC leakage, required for some older chargers or those without their own DC leakage sensor. When in doubt, check the charger specification: if it does not include integral 6mA DC leakage protection, use a B-type device.
What is the difference between B-curve and C-curve MCBs and RCBOs?
B-curve devices trip on magnetic (instantaneous) overcurrent at 3–5× rated current and are standard for most domestic circuits. C-curve devices trip at 5–10× rated current, providing greater tolerance for the inrush current of motors, contactors, and certain EV charger types with high startup currents. The charger manufacturer's documentation will specify which curve is required; if unspecified, B-curve is generally the default for domestic 7kW installations.
How do surge protection devices (SPDs) protect EV chargers?
Type 2 SPDs divert transient overvoltages — caused by indirect lightning strikes, utility grid switching, or nearby inductive loads — safely to earth before they can damage the charger's control electronics. SPDs should be installed as close to the equipment being protected as possible. They do not protect against direct lightning strikes (Type 1 SPD at the main incomer is required for that), but they are highly effective against the more common indirect transient events.
Can I install WCED products myself, or do I need a qualified electrician?
All WCED electrical protection products must be installed by a qualified electrician in accordance with BS 7671. EV charger installations in the UK are also subject to notification requirements under Part P of the Building Regulations (England and Wales) and equivalent Scottish/Northern Irish regulations. DIY electrical installation of EV charging equipment is not permitted under current UK regulations.
How often should WCED protection devices be tested?
RCDs and RCBOs should be tested using the built-in test button at least every 6 months as part of routine maintenance — push the test button and confirm the device trips. A full periodic inspection of the installation, including verification of tripping times, should be conducted by a qualified electrician at intervals recommended in BS 7671 — typically every 5–10 years for domestic installations and more frequently for commercial or high-use sites.
Are WCED products compliant with UK wiring regulations?
Yes. All WCED products are designed and tested to comply with the relevant sections of BS 7671:2018+A2:2022 (18th Edition with Amendment 2) and BS EN 61439-3 (distribution board standard). PME fault detection units are specifically designed to meet Regulation 722.411.4.1 for EV charger installations.