Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

As a front - line maintenance technician, I deal with current transformers (CTs) daily. CTs convert high - magnitude primary current to low - magnitude secondary current for substation/line protection and measurement, operating in series long - term. However, they face faults from external (unbalanced loads, wrong wiring, etc.) and internal (insulation defects) issues. These faults, like secondary open - circuits or insulation breakdown, harm measurement accuracy, protection operation, and grid

With the development of modern economy and science and technology, photoelectric current transformers (PECTs) have fully transitioned from the trial operation stage to practical application. As a front - line testing personnel, I deeply feel their importance in the power system during daily work. I also realize the necessity of conducting in - depth research on their testing systems and calibration methods. This not only promotes the engineering application of PECTs but also enables the accurate

Automatic backup switching (ABTS) devices are core components ensuring the safe, reliable, and stable operation of factory power grids. Their startup logic strictly follows the dual criteria of "loss of voltage in the working power supply + no - current detection", effectively avoiding misjudgments caused by secondary disconnection of voltage transformers (VTs) or maloperations of ABTS due to secondary circuit faults of current transformers (CTs). The activation condition requires both "no volta

Practical Experience Sharing from an Electrical Engineer in the FieldBy Oliver, 8 Years in the Electrical IndustryHi everyone, I'm Oliver, and I've been working in the electrical industry for 8 years.From early involvement in substation commissioning and equipment inspection, to now managing the maintenance and fault analysis of entire power systems, one of the most frequently encountered devices in my work has been the voltage transformer (VT / PT).Recently, a friend who's just starting out ask

By James, 10 Years of Electrical Equipment Maintenance ExperienceHi everyone, I’m James, and I’ve been working in electrical equipment fault repair for 10 years.Over the past decade, I’ve worked in factories, substations, and distribution rooms of all sizes, involved in the installation, commissioning, maintenance, and troubleshooting of dry-type transformers. Dry-type transformers are among the most common electrical devices we deal with on a daily basis.Today, a n

1 Pre - commissioning InspectionAs a front - line tester, before formally commissioning a dry - type transformer, I need to carry out a comprehensive and systematic inspection. First, I conduct a visual inspection of the transformer body and its accessories, carefully checking for mechanical damage or deformation. Then, I check whether the leads of the high - and low - voltage windings are firmly connected and whether the bolt tightening torque meets the standard requirements (usually 40 - 60N&a

1 Pre - installation PreparationAs a front - line installer, I know very well that the preparation work before installing a dry - type transformer must be thorough. First, I will carefully review the design drawings and technical documents, and check one by one the technical parameters such as the model specification, rated capacity, and voltage level of the transformer to ensure they are in full compliance with the design requirements. Then, I will conduct an unpacking inspection of the transfo

In recent years, as distribution automation advances, load switches see wider use in distribution lines. Yet, mechanical - failure - induced accidents are on the rise, burdening line operation and maintenance.Poor mechanical performance is the main cause of switch faults. Many scholars study large - scale switchgear operation, using methods like coil current detection, vibration signal analysis, switch travel testing, ultrasonic flaw detection, and infrared thermometry. Motor - current - based s

As a technician with years of on-site experience in power testing, I understand the importance and complexity of load switch testing. Below, I combine practical work experience to elaborate on the full process of load switch testing, from testing items and methods to equipment and procedural specifications.I. Routine Electrical Performance Testing(1) Loop Resistance TestLoop resistance is a core indicator for evaluating a load switch's conductivity. I strictly follow GB/T 3804 and GB 1984 standa

As a frontline operator who deals with smart electricity meters daily, I’m well - versed in the design and operational norms of load switches (both internal and external) in these meters. Below, I’ll break down the technical requirements and practical key points based on my on - site experience for easy reference.I. Basic Understanding of Internal and External Load SwitchesIn the type specifications for single - phase and three - phase smart electricity meters (such as enviro