LMZ(J)1-0.72 Current Transformer

Measure DC resistance: Use a bridge to measure the DC resistance of each high- and low-voltage winding. Check whether the resistance values among phases are balanced and consistent with the manufacturer’s original data. If phase resistance cannot be measured directly, line resistance may be measured instead. The DC resistance values can indicate whether the windings are intact, whether there are short circuits or open circuits, and whether the contact resistance of the tap changer is normal. If

Front-panel visible wiring: During manual wiring (not using templates or molds), wiring must be straight, neat, closely attached to the mounting surface, rationally routed, and with secure connections that facilitate maintenance. Wiring channels should be minimized as much as possible. Within the same channel, bottom-layer conductors shall be grouped by main and control circuits, arranged in a single-layer parallel dense layout or bundled, and kept closely attached to the mounting surface. Condu

The tap changer operating handle shall be equipped with a protective cover. The flange at the handle shall be well sealed with no oil leakage. Locking screws shall securely fasten both the handle and the drive mechanism, and the handle rotation shall be smooth without binding. The position indicator on the handle shall be clear, accurate, and consistent with the tap voltage regulation range of the winding. Limit stops shall be provided at both extreme positions. The insulating cylinder of the t

Common inverter faults mainly include overcurrent, short circuit, ground fault, overvoltage, undervoltage, phase loss, overheating, overload, CPU malfunction, and communication errors. Modern inverters are equipped with comprehensive self-diagnostic, protection, and alarm functions. When any of these faults occurs, the inverter will immediately trigger an alarm or shut down automatically for protection, displaying a fault code or fault type. In most cases, the fault cause can be quickly identifi

Causes of Dielectric Withstand Failure in Vacuum Circuit Breakers: Surface contamination: The product must be thoroughly cleaned before dielectric withstand testing to remove any dirt or contaminants.Dielectric withstand tests for circuit breakers include both power-frequency withstand voltage and lightning impulse withstand voltage. These tests must be performed separately for phase-to-phase and pole-to-pole (across the vacuum interrupter) configurations.Circuit breakers are recommended to be t

There are many taboos and problematic practices in the installation of distribution boards and cabinets that must be noted. Especially in certain areas, improper operations during installation may lead to serious consequences. For cases where the precautions were not followed, some corrective measures are also provided here to remedy previous mistakes. Let’s follow along and take a look at common installation taboos from manufacturers regarding distribution boxes and cabinets!1. Taboo: Lighting

I. Background and Challenges​Shore power systems have become core technical equipment for ports to reduce carbon emissions and noise pollution. However, these systems face two major challenges in the harsh operational environment of ports:​Severe Environmental Corrosion: High humidity and salt spray in port areas cause serious corrosion to metal components and enclosures of electrical equipment, significantly impacting electrical lifespan and operational reliability.​High Switching Requirements:

Issue Overview​The 10kV air compressor starting system of a company utilizes the ABB vacuum contactor KC2 as the control component for the operating circuit. The dedicated wide-voltage power supply module paired with this contactor presents the following issues:​Frequent failures: The power supply module fails to properly transition the voltage from 300V to 12V, resulting in fuse blowouts.​Poor heat dissipation: Enclosed installation of the module leads to insufficient heat dissipation, acceler

1.Project BackgroundA coal conveying system comprises 15 belt conveyors driven by medium-voltage motors. The system operates under complex conditions, with motors often subjected to heavy loads and frequent starts. To address these challenges and achieve effective control and reliable protection during motor startup, the project comprehensively adopts Vacuum Contactor-Fuse (VCF) combination devices for the 6kV medium-voltage motor power distribution. This solution details the technical features,