How does NEV affect electronic systems ? Systems are working fine even if we interchange Phase and neutral. After goggling, I am in impression that susceptibility to NEV is mainly due to electronic design issues (like PWM feedback of SMPS referenced to chassis) and designs after 2000 are almost immune to NEV. Similarly I could not find any authenticated info / standard on NEV limit. People use 0.1, 1%, 10V, e.t.c., but did not get on what technical criteria are they selected. Please share our thoughts.