The zero current transformers are used indoor. They are used for over driven current protection in the electric non-useful-ground netural system up to rated frequency 50HZ or 60HZ and rated voltage 35kv.

Technical data :

type	Resistance of the connection line(Ω)	Startup current of the relay(A)	Sensitive	Scale of relay(A)	Rated current ratio(A)
LJ-75	1	0.1	6~10	0.1~0.2	30/1