What is a Matt:e R or Matt:e T device?

The Matt:e device constantly measures the voltage of the EV Chargepoint circuit to ensure that the voltage is within a pre-set, safe operating limit.  If the Matt:e device detects voltage outside of this range, it may indicate a PEN conductor fault, which may be a loss of effective earth.

In this scenario, the Matt:e device will temporarily disconnect the charger to ensure that customers are not at risk of electrocution. This piece of hardware is required in the majority of installations and is required to ensure the charger is earthed to an effective standard as per regulations. 

If you have an existing earthing system (TT earth electrode), a Matt:e device may not be required, but this will be assessed on your Virtual Home Check.