For the latest version of its Pulsar Plus EV charging station
, Wallbox has designed and implemented a protective measure in line with the BS 7671:2018 amendment1:2020. For full compliance information please click here
How does the Pulsar Plus implement earthing protection?
As the amendment states, when the voltage between the line and the neutral surpasses a certain range, the charger shall trip and open any contactor or relay so any load below the charger is isolated (for example, the car). The measurement of the voltage between line and neutral was already present in the Pulsar Plus. In this variant, a set of limits controlled by software are applied according to the BS 7671. To avoid any false negative, the tripping zone considers safe tolerances, resulting in the following:
Higher voltage acceptable 253 V
Tripping zone ≥ 248 V
Lower voltage acceptable 207 V
Tripping zone ≤ 212 V
This means that when the voltage measured by the chargers is within the tripping zone, it can trip in the following fashion: the closer to the limit the higher the probability to trip.
Of course, once the limit stated by the BS 7671 is reached, the charger always trips.
What happens when the charger is powered on?
Once it boots, the charger provides isolation; it waits while the voltage measurements are stabilized. After this it reads the voltage measurements for four seconds in a row and evaluates the results.
What happens during runtime?
- If there are more reads within the allowed range, it is considered a safe scenario and the charger goes to ready mode and the halo turns green. Then the Protective Earth is connected to the charger and to the charging cable.
- If it is considered a PEN fault scenario, the charger goes to error mode and the halo turns red.
The charger is constantly evaluating the voltage between the line and the neutral. At intervals of a second, the charger determines if it is under the PEN fault scenario or the safe scenario. Following the BS 7671:2018 amendment1:2020, the charger trips after five seconds of a PEN fault.
What happens when a PEN fault occurs?
If a PEN fault occurs and the charger trips, it is notified by turning the halo’s colour red on the charger. The charger then stays in error mode until it is manually reset. This action can be done via the following:
- by powering the charger off and on
- the myWallbox App
- the myWallbox portal
The restart can be performed remotely via the app and portal, if the charger is connected online. It is important to note that the Pulsar Plus charger with earthing protection performs as described on single phase installations only.
View the Pulsar Plus EV charging station with PEN fault detection