I. Project Overview

This project was completed by Nanke Electric, delivering, installing, commissioning, and putting into operation the test equipment for Junlang Electric Co., Ltd. Junlang Electric was founded in 2009 in Yueqing City, Wenzhou, Zhejiang Province, specializing in the R&D, production, and sales of high- and low-voltage electrical equipment, with flagship products including the S20 series energy-saving transformers and Scb13 epoxy-resin cast dry-type transformers.

To address the cumbersome operations and low efficiency of traditional transformer testing, we deployed a fully automated distribution transformer testing system to meet the company’s requirements for factory acceptance tests.

II. Maximum Testing Capacity

The system operates at frequencies of 50–60 Hz and can perform tests on transformers with various voltage levels, capacities, and impedance parameters, offering broad compatibility. Specific parameters are as follows:

High voltage: 6 kV; low voltage: 0.4 kV/0.8 kV; maximum test capacity: 3,150 kVA; compatible impedance: 4%–6%

High voltage: 10 kV; low voltage: 0.4 kV/0.8 kV; maximum test capacity: 6,300 kVA; compatible impedance: 4%–8%

High voltage: 20 kV; low voltage: 0.4 kV/0.8 kV; maximum test capacity: 6,300 kVA; compatible impedance: 5%–8%

High voltage: 35–38.5 kV; low voltage: 0.4 kV/0.69 kV/0.8 kV/1.14 kV; maximum test capacity: 6,300 kVA; compatible impedance: 6%–10%

Single-phase transformers: rated capacity up to 333 kVA; high-voltage side supports 34.5 kV, 23 kV, and 13.8 kV; low-voltage side ≤ 0.48 kV; impedance voltage: 2%–6%

 III. Test Items

This highly integrated system can complete all six standard transformer tests in one go, comprehensively covering all mandatory factory inspection items:

(1) No-load test

(2) Load test

(3) Induction test

(4) Temperature-rise test

(5) Partial-discharge test

(6) Power-frequency withstand voltage test

IV. Project Highlights

(1) Fully automated operation throughout the entire process—single wiring completes all tests, significantly improving quality and efficiency.

The system supports single-wiring and eliminates the need for disassembly during the entire testing procedure. After staff enter basic parameters such as transformer capacity and voltage, the equipment automatically switches current transformer ranges, adjusts the voltage regulator, and executes the test sequence. Test data is recorded automatically throughout, and upon completion, a test report can be directly exported, reducing manual intervention.

(2) Intelligent data management ensures precise and traceable test results.

The equipment is equipped with a high-precision data acquisition module and a power analysis unit, providing real-time display of voltage, current, power, frequency, impedance, losses, and other test data, while automatically converting values under rated operating conditions and standard temperatures. The system supports data locking, local storage, and historical record retrieval, facilitating product quality traceability and documentation retention.

(3) Strong adaptability, covering testing of all product categories.

The system offers wide-ranging compatibility in terms of voltage, capacity, and impedance, supporting mainstream products such as Junlang’s S20 energy-saving transformers and Scb13 dry-type transformers, while also accommodating single-phase transformer testing. A single set of equipment can meet routine quality inspections within the plant, demonstrating strong practicality.

V. Commissioning Information

Client Company: Junlang Electric Co., Ltd.

Commissioning Date: April 2026