In residential installations, where the neutral conductor is grounded to the building's entrance pattern, the DPS are connected between the phase conductors and the grounding bar of the switchboard. In these cases, DPS is not installed between neutral and the ground bus. The DPS can be connected before or after the general protection device of the switchgear, but it is generally recommended to connect them before protection. The DPS manufacturer should be consulted to verify the need or not to install overcurrent protection (circuit breaker or fuse) for the protection of the DPS. If necessary, the manufacturer must inform the type and characteristics of this protection. The length of each conductor connecting the DPS to the phase conductor plus the length of each conductor connecting the DPS to the grounding bar must be as short as possible, not to exceed 50 cm. These curved connections and loops must also be avoided. The nominal section of the conductors connecting the DPS to the phases and to the grounding bar must never be less than 4 mm2, it is recommended that it be, at least, equal to the section of the phase conductors.
