New Medium-Voltage Switchgear Solution

Grid digital transformation and fully automated switchgear: AI-enabled digitized devices for fault detection, protection, and automated distribution network control.

What Are the Discs Inside a Distribution Cabinet?

Identification and technical overview of a three-phase autotransformer in a distribution cabinet, covering working principle, structural features, and voltage regulation use cases.

Grid Harmonics and Power Quality Effects

Technical overview of grid harmonics: definitions, causes, key terms and THDu limits under China's standard GB/T 14549-1993 for power quality assessment.

Firestopping Requirements for Cable Trays and Wall/Slab Penetrations

Technical guide to firestopping cable tray and slab penetrations in electrical shafts; specifies materials, packing limits, waterstop heights and installation sequence.

Two Automation Modes for Central Control Stations

Technical overview of central control station for unmanned substations: compares hierarchical management mode and centralized control mode, with SCADA/dispatch integration.

Optimal Location for Low-Voltage Power Factor Panels

Comparison of PFC cabinet installation upstream vs downstream in a distribution room, assessing through-busbar capacity, ambient temperature impact, and correction effectiveness.

Purpose and Requirements of Automatic Reclosers

Overview of automatic reclosers, advantages, risks, and implementation principles for single-phase adaptive reclosing and comprehensive automatic reclosing in power systems.

Power Room Shutdown and Re-energization Sequence

Step-by-step shutdown and re-energization procedures for distribution switchgear, specifying low-voltage vs high-voltage isolation order, circuit breaker operations and fault recovery.

Are AC Terminals the Same as AC Cables? Inverter Installation Steps

Technical guide to inverter AC cable selection for residential and commercial installations, comparing copper and aluminum conductors and outlining wiring and commissioning steps.

Substation Secondary Systems: Common Equipment

Technical overview of terminal block design and front panel layout principles for secondary equipment, covering terminal types, arrangement, and panel diagrams.

When to De-energize a Transformer for Inspection

Classification of transformer defects (urgent, major, general), emergency fault indicators, response time targets, and de-energization criteria for oil and cooling failures.

Breaker Categories and 10/350, 8/20 Surge Parameters

Technical overview of breakers (CAT A/B), RCBO/RCCB/RCD, surge protector waveforms (10/350, 8/20), IP ratings for switchgear, and transformer hum causes and mitigation.

Responding to High-Power Outages in Outdoor Construction

Review of portable power options and large-capacity mobile energy stations for prolonged, high-power outages: specifications, output, cycle life, safety, and deployment.

Distribution Room vs Distribution House vs Distribution Compartment

Technical overview of distribution room, house, and compartment classifications, functions, voltage levels and electricity user categories for utilities.

40 Essential Secondary Electrical Circuit Concepts

Guide to 40 secondary circuits concepts for electrical technicians, covering relay protection, zero/negative-sequence schemes, transformer testing and protection settings.

Power Distribution for Small-Medium Container Systems

Overview of 250 kWh–2 MWh energy-storage container: AC distribution, UPS-backed circuits for BMS/fire systems, explosion-proof lighting, grounding and mounting specs.

Key Technologies for Grid-Connected Energy Storage Systems

Technical overview of residential and C&I energy storage systems, energy storage meter functions and grid-side metering, plus ADL series DIN-rail meter models.

How to Read Electrical Secondary Circuit Diagrams

Technical guide to reading a secondary circuit diagram in power systems: interpret AC circuits before DC, locate AC power sources and coils, and verify relay contacts.

Active Distribution Network Control for New Power Systems

Overview of active distribution network concepts, grid digital transformation, and technologies for new power systems including DER, storage, VPP, and intelligent sensing.

Resolving Islanding in Grid-Tied Inverters

Technical guide to diagnosing islanding in grid-tied inverters: inspection steps, islanding detection and islanding box monitoring of reflected power (Ql) and capacitive power (Qc).