Documents 11kV Cast-Resin CT Burden Calculation Guide: IEC 61869 Compliance for Metering & Protection Circuits May 17, 2026 / April 22, 2026 by tianming 5. Burden Calculation The burden of a current transformer (CT) is the total impedance presented to its secondary winding, comprising connected devices (relays, meters, etc.) and wiring resistance. Accurate burden calculation ensures CTs operate within accuracy limits specified by standards such as IEC 61869 or IEEE C57.13. Burden is typically expressed in volt-amperes (VA) at […] Read more »
3kV-12kV Indoor CTs LAJ-10 / LFZBJ-10 Wall-Through Epoxy Cast-Resin Current Transformer May 16, 2026 / July 20, 2026 by tianming Product Overview The LAJ-10 / LFZBJ-10 current transformer is an indoor epoxy cast-resin wall-through current transformer designed for medium-voltage switchgear applications. These two model references can be combined into one product family because both are used for current measurement, electric energy metering, and relay protection in indoor AC power systems. For international project documentation, the […] Read more »
3kV-12kV Indoor CTs LMZB6-10Q(L)/150 Cast-Resin Cable/Busbar-Through Current Transformer May 16, 2026 / July 20, 2026 by tianming LMZB6-10Q(L)/150 indoor fully enclosed epoxy cast-resin cable/busbar-through current transformer for 10kV, 11kV and 12kV class switchgear. Designed for high-current measurement, energy metering and relay protection, with 1500A–5000A current range, 1A or 5A secondary output, 12/42/75kV insulation level and 0.2S/0.5/5P accuracy options. Read more »
3kV-12kV Indoor CTs LMZB6-10Q/160 Epoxy Cast-Resin Cable/Busbar-Through Current Transformer May 16, 2026 / July 20, 2026 by tianming LMZB6-10Q / 160 indoor epoxy cast-resin cable/busbar-through current transformer for 10kV, 11kV and 12kV class switchgear. Designed for high-current measurement, energy metering and relay protection, with 1000A–5000A current range, 1A or 5A secondary output, 12/42/75kV insulation level and 0.2(S)/0.5(S)/5(10)P accuracy options. Read more »
Documents SEL-351 21kV Cast-Resin Voltage Transformer for Substation Metering and Protection – IEC 61869-3 Certified May 16, 2026 / May 2, 2026 by tianming SEL-351 21kV Cast-Resin Voltage Transformer for Substation Metering and Protection – IEC 61869-3 Certified Introduction to the SEL-351 Voltage Transformer The SEL-351 is a 21kV (IEC-rated) cast-resin voltage transformer (VT) engineered for high-reliability metering and protective relaying applications in medium-voltage power systems. Designed in strict accordance with IEC 61869-3 and GB/T 20840.3, this instrument transformer […] Read more »
3kV-12kV Indoor CTs LMZBJ17-12L(Q)/170 Epoxy Cast-Resin Cable/Busbar-Through Current Transformer May 16, 2026 / July 20, 2026 by tianming LMZBJ17-12L / LMZBJ17-12Q / 170 indoor epoxy cast-resin cable/busbar-through current transformer for 10kV, 11kV and 12kV class switchgear. Combines Q/170 and Q/L variants, with 1500A-5000A current range, 1A or 5A secondary output, 12/42/75kV insulation level and 0.2S/0.5/5P protection combinations. Read more »
3kV-12kV Indoor CTs LMZB3-10Q/137 Epoxy Cast-Resin Cable Busbar-Through Current Transformer May 16, 2026 / July 20, 2026 by tianming LMZB3-10Q/137 indoor epoxy cast-resin cable/busbar-through current transformer for 10kV, 11kV and 12kV class medium-voltage switchgear. Designed for high-current measurement, energy metering and relay protection, with 1500A–5000A current range, Ø137 aperture, 12/42/75kV insulation level, 240mm creepage distance and 0.2/5P, 0.5/5P or 5P/5P accuracy combinations. Read more »
Documents JWD-10 11kV Outdoor Current Transformer: IEC-Compliant 0.2S Metering & Protection Class Selection May 16, 2026 / April 22, 2026 by tianming Introduction The JWD-10 current transformer is a critical component in medium-voltage power systems, specifically engineered for reliable and accurate current measurement and protection in 10 kV networks. As a resin-insulated, outdoor-type current transformer, the JWD-10 combines robust mechanical construction with high dielectric strength, ensuring long-term performance under demanding environmental conditions. Its primary applications include integration […] Read more »
3kV-12kV Indoor CTs LMZD2-10Q Epoxy Cast-Resin Cable / Busbar-Through Wall-Mounted CTs May 16, 2026 / July 20, 2026 by tianming LMZD2-10Q indoor epoxy cast-resin cable/busbar-through wall-mounted current transformer for 10kV, 11kV and 12kV class medium-voltage switchgear. Designed for high-current measurement, energy metering and relay protection, with 1200A–5000A primary current range, 12/42/75kV insulation level, 255mm creepage distance, and 0.2/5P, 0.5/5P or 5P/5P accuracy combinations. Read more »
Documents Instrument Transformer Maintenance & Diagnostic Testing: Tan δ, PD, Ratio & Excitation Guide (IEC 61869, IEEE C57.13) May 16, 2026 by tianming Instrument Transformer Maintenance & Diagnostic Testing: Tan δ, PD, Ratio & Excitation Guide (IEC 61869, IEEE C57.13) Meta Description: Comprehensive guide on instrument transformer maintenance and diagnostic testing. Covers tan δ, partial discharge, ratio, excitation, and insulation resistance testing per IEC 61869 and IEEE C57.13. Includes testing procedures, acceptance criteria, trend analysis, and troubleshooting for […] Read more »
Documents LFS-10 11kV Cast-Resin Current Transformer Compliant with IEC 61869-2 for Metering and Protection for substation appl… May 16, 2026 / May 2, 2026 by tianming IEC 61869-2 Certified 11kV Cast-Resin Current Transformer LFS-10 for Metering & Protection Applications Introduction to the LFS-10 Current Transformer The LFS-10 is a medium-voltage cast-resin current transformer engineered for precision current measurement and protective relaying in 11kV (IEC) / 10kV (domestic) electrical networks. Designed for both indoor and outdoor deployment, this instrument leverages vacuum pressure […] Read more »
Documents LB-10W 11kV Current Transformer Selection: IEC-Compliant Cast-Resin CT for Metering & Protection May 16, 2026 / April 22, 2026 by tianming Introduction The LB-10W Current Transformer (CT) is a critical component in medium-voltage power systems, specifically engineered for reliable and accurate current measurement and protection applications at system voltages up to 10 kV. Designed with robust insulation and high thermal stability, the LB-10W ensures safe operation under demanding electrical conditions while maintaining precise performance over extended […] Read more »
