Frequently Asked Questions

Not when you use a matt-e connection unit. Our built-in O-PEN® technology detects PME faults and isolates the supply automatically, eliminating the need for earth rods. This saves approximately two hours of labour per installation and avoids the need for ground surveys or civil works.

A Broken PEN fault occurs when the combined Protective Earth and Neutral conductor fails somewhere in the external distribution network. When this happens, the metalwork of the EV charger and any bonded equipment can become live at up to 230V. Because the fault originates on the supply side, standard MCBs and RCDs will not detect it. matt-e units specifically identify this condition and immediately cut power.

If the unit trips and will not reset, it may have detected a genuine supply-side fault. Check that the supply is healthy and that all connections are secure. If the problem persists, contact our technical support team on 01543 227290 who can advise on next steps.

Yes. matt-e units can be mounted directly onto metal-clad structures without additional earthing requirements, as the O-PEN® technology manages the protective earth connection independently.

Standard EV units protect individual charger circuits at the point of connection. The Guardian provides site-wide protection at the main distribution board, monitoring power quality across an entire building's infrastructure. It supports multiple downstream charge points without requiring individual protection boxes at each one.

The Guardian includes IoT connectivity and sends SMS and email alerts to nominated contacts when it detects a fault condition such as a broken PEN conductor, loss of neutral, or voltage anomalies. Building managers can also access a cloud portal to monitor status remotely.

Yes. matt-e manufactures dedicated three-phase units (EVU and ARD connection centre series) as well as three-phase Guardian units, designed for commercial premises, car parks, fleet depots and other large-scale EV charging installations.

A flashing red LED indicates that the PEN fault protection has detected a supply-side fault. Power will be isolated automatically. The fault should be investigated by a qualified electrical contractor or reported to the Distribution Network Operator (DNO). Contact our technical team on 01543 227290 for guidance.

Ensure the red isolator is switched on. Turn the rotary isolator counter-clockwise to the test position. Switch the main isolator off. Return the rotary isolator to the normal position. Then reactivate the red mains isolator. If the unit still does not reset, contact our technical support team.