*2.2. Charging Station in Mode 3 According to IEC 61851-1 Standard*

For charging EV in AC, the most used solution is mode 3 because it fully guarantees the safety of people. The station has a charging controller that, via a control pilot, can communicate with vehicle and checks (before starting charging process) the following:


The communication signal sent by the charging station to the EV on the control pilot and earth has a square wave shape of 1 kHz frequency and ±12.0–±0.4 V voltage range. The typically control pilot circuit according to IEC61851-1 is illustrated in Figure 2. The stage of charging cycle is identified by the station charger controller through positive voltage level of communication signal level, as follow:


**Figure 2.** Typical control pilot circuit according to IEC61851-1.

The EVSE can send information through the duty cycle of the communication signal to the EV about the maximum current supported by the cable used. Consequently, the EV battery management system interprets the Control Pilot signal to limit charge rate.
