Zero sequence current transformer is suitable for use with DD-11/60 or DD-1/60 type relay and signal device in small grounding current system with rated frequency 50/60Hz and rated voltage 35kV and below, for residual (zero sequence) current detection and grounding protection, and at the same time make device components move, to achieve protection and monitoring. LXK series residual (zero sequence) current transformers are cable type resin casting insulation indoor products, this series of zero sequence current transformers are open and close, epoxy resin casting structure, installation can be divided into two parts, and then merged into one, easy to install, Transformer inner diameter is φ 80, φ100, φ120, φ140, φ150, φ160, φ180, φ200, φ240, φ260, φ300 several specifications 1. The core of the current transformer has adoped amorphous alloy, it has high magnetic permeability, low saturation induction density and good stability. 2. High quality silicon steel sheet is taken to be the core of windings protection, which ensures the high accuracy limit factor. 3. The circular ring core and secondary windings are poured by high quality expoxies resin or polyurethane or silicon rubber in the fire retardant plastic casing, which has the characteristic of moisture proof, stable performance and dispensing with maintenance. the cable can cross the current transformer through its internal poles quickly and uniformly. Ambient temperature:-10ºC-+40ºC Relative humidity:The average humidity of a day should be no more than 95%. The average humidity of a month should be no more than 90%. Earthquake intensity: not exceed 8 degrees. Saturated vapor pressure the average pressure of a day should be no more than 2.2kPa; the average pressure of a month should be no more Than1.8Kpa; The height above sea level:≤1000 m (Except special requirements) It should be installed in the places without fire, explosion, serious filth, and chemical erosion and violent vibration.