ECG KOKUSAI

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This device is ideal for evaluating the insulation reliability of coils used in inverter motors, home appliances, automobiles, and industrial equipment. In inverter-driven coils—such as those found in EV and HEV drive motors, automotive motors, and industrial motors—partial discharges caused by high-voltage spikes are the primary cause of insulation degradation. This device can highly sensitively measure and evaluate partial discharges generated while an AC voltage is applied, and supports insulation evaluation for a wide range of high-voltage products, including power transformers, switching power transformers, power semiconductors, insulating films, and insulating materials.

Its most notable feature is the use of a microwave patch antenna system. By directly detecting the electromagnetic waves generated by the coil while an AC voltage is applied, it achieves highly sensitive partial discharge measurement that is less susceptible to interference from the test circuit. It is easy to operate even without specialized knowledge, and can be easily integrated into production lines and automated. Equipped with a wide range of graphical analysis functions—such as applied voltage-PD characteristics and cumulative discharge frequency—it visualizes the discharge initiation voltage (PDIV), extinction voltage (PDEV), discharge intensity, and number of occurrences in real time. This also helps reduce testing time and lower costs.

Production Engineering Department
Quality Assurance Department
Maintenance Department
Development Department

This system is ideal for production lines manufacturing wound coils—such as motors, transformers, and solenoids—where operators wish to consolidate multiple inspection processes. Since a single unit can perform all four types of tests—pulse testing, DC resistance testing, AC withstand voltage testing, and insulation resistance testing—it directly contributes to space savings and cost reductions in inspection equipment. It features a built-in 10-channel circuit switcher and supports testing of multi-terminal coils. It is widely adopted for 100% inspection on mass production lines by manufacturers of automobiles, home appliances, and industrial equipment.

This “all-in-one winding tester” combines four types of tests into a single unit. It features a built-in 10-channel circuit switcher, allowing users to freely configure test sequences of up to 100 steps. By adding an optional PD sensor, the unit can also perform impulse partial discharge (PD) testing, enabling comprehensive, advanced insulation evaluation of EV and HV motors with a single unit. Furthermore, when connected to a LCR meter, it can measure inductance, and when connected to our RDT-308, it can automatically perform rotation direction tests. Its high expandability is its greatest strength.

Production Engineering Department
Quality Assurance Department
Maintenance Department
Development Department

It is ideal for quality inspection of chip power inductors and ultra-compact coils used in smartphones, PCs, automotive electronics, and IoT devices. These coils, which have few turns and extremely low inductance, were difficult to inspect using conventional impulse testers because they could not apply sufficient voltage. This device enables the application of high voltage to coils with ultra-low inductance as low as 100 nH, allowing for 100% inspection and quality assurance through impulse testing (layer short detection) on the production line.

Our proprietary 4-terminal testing method enables the application of high-voltage pulses to ultra-low-inductance coils. With ultra-high-speed testing—10 msec without evaluation and 18 msec with evaluation—which represents the industry’s highest standard, this directly contributes to reducing takt time on mass production lines. High-resolution 300 MHz sampling and 12-bit voltage resolution ensure high-precision detection of even minute insulation defects. The lineup includes two models—the DWX-300LI3a (max. 300 V) and the DWX-01LI3a (max. 1000 V)—allowing you to select the optimal test voltage based on the coil characteristics.

This device is ideal for quality inspection of stator coils on motor production lines. In the manufacturing process of three-phase motors, errors in the direction of magnetic field rotation (CW/CCW) or partial connection defects caused by wiring errors or incorrect winding can lead to serious quality issues. This device applies a three-phase excitation signal to the stator coil and automatically determines the direction, strength, and distribution of the magnetic field. It is widely used in a variety of applications, ranging from 100% inspection on mass production lines for motors used in automobiles, home appliances, industrial equipment, and robots, to research and development facilities.

Equipped with two test modes, it supports both simple and precise inspections depending on the application. Test Mode 1 quickly determines magnetic field strength and rotation direction (CW/CCW). Test Mode 2 precisely measures magnetic field distribution (phase and strength) at up to 32 points, enabling high-precision detection of partial wiring defects and winding errors. Up to 10 test conditions can be registered, making it easy to handle a wide variety of products. With support for automation via RS-232C communication and a compact design (1.8 kg), integration into production lines is seamless.

Equipped with two test modes, it supports both simple and precise inspections depending on the application. Test Mode 1 quickly determines magnetic field strength and rotation direction (CW/CCW). Test Mode 2 precisely measures magnetic field distribution (phase and strength) at up to 32 points, enabling high-precision detection of partial wiring defects and winding errors. Up to 10 test conditions can be registered, making it easy to handle a wide variety of products. With support for automation via RS-232C communication and a compact design (1.8 kg), integration into production lines is seamless.

Production Engineering Department
Quality Assurance Department
Maintenance Department
Development Department

It plays a key role in the production lines and quality inspection processes of all electrical products that use wound coils, such as motors, transformers, solenoids, and ignition coils. In particular, for inverter-driven motors used in EVs and HVs (electric and hybrid vehicles), partial discharges (corona discharges) generated inside the windings due to high voltage spikes are a major cause of insulation degradation. As a result, the DWIT-05PD—which can perform partial discharge testing simultaneously with conventional layer short testing—is gaining attention as the new standard for manufacturing quality assurance. It has been adopted in mass-production inspection lines across a wide range of industries, including automotive, home appliances, industrial equipment, and robotics, and is capable of performing 100% inspection inline.

By applying a high-voltage pulse to a coil and comparing the response waveforms, layer shorts are detected with high accuracy. Furthermore, this single unit can simultaneously perform conventional impulse winding tests (for rare short detection) and partial discharge (PD) tests. Thanks to its proprietary detection circuit, the system highly sensitively detects partial discharges—which are subtle signs of insulation coating degradation—and completes the reliability evaluation of coils for inverter-driven motors, such as those used in EVs and HVs, in a single process. In recent years, there has also been growing interest in insulation testing for materials such as insulating paper and coatings; this system is capable of handling everything from small-lot, high-variety production to 100% inspection of mass-produced items, as well as insulation evaluation of film materials.