AIC tech Inc. List of Products and Services

This document explains key capacitor characteristics such as "capacitance," "impedance," and "leakage current," along with examples and data. Please feel free to download and take a look. 【Contents】 ■ Capacitance ■ Impedance ■ Leakage Current ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

You can consult with us for technical advice and purchase Jianghai-made electric double-layer capacitors (EDLC) / lithium-ion capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power failures, UPS, and various backup power supplies, leveraging the high input/output characteristics of capacitors. ◆ Cells are available under the JIANGHAI CAPACITOR brand of our group company, and we can also provide modules that are designed and produced in-house. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

You can consult and purchase Jianghai-made electric double-layer capacitors (EDLC) and lithium-ion capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power interruptions, UPS, and various backup power supplies, leveraging the high input-output characteristics of capacitors. ◆ Cells are available under the JIANGHAI CAPACITOR brand from our group company, and we can also provide modules designed and produced in-house. *For more details, please refer to the PDF materials or feel free to contact us.

• Capacitor

You can consult with us for technical advice and purchase Jianghai-made electric double-layer capacitors (EDLC) / lithium-ion capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power failures, UPS, and various backup power supplies, leveraging the high input/output characteristics of the capacitors. ◆ Cells are provided under the JIANGHAI CAPACITOR brand from our group company, and we can also offer modules designed and produced in-house. *For more details, please refer to the PDF materials or feel free to contact us.

• Capacitor

Failures of capacitors can be attributed to environmental factors such as temperature, atmospheric pressure, and vibration, as well as electrical factors like operating voltage, ripple current, and charge/discharge duty cycle. As the temperature rises, the chemical reactions within the capacitor accelerate, leading to a shorter lifespan. It is important to consider not only the ambient temperature but also various factors such as heat generation from ripple current and radiant heat from other heat-generating components. This document covers not only how to select and use capacitors but also includes information on lifespan estimation, failure modes, and failure mechanisms. We encourage you to read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Failure Mechanisms ■ Lifespan Estimation ■ Selection and Usage ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

The function of a capacitor is to "not allow direct current to pass," "instantaneously store and release charge," and "allow alternating current to pass." When these functions are lost, it results in failure. The failure rate is defined as "the ratio of a system or component that, after operating without failure for a certain period, experiences a failure within the subsequent unit period." In other words, the failure rate is "the rate at which failures occur" and is a quantitative measure of reliability. This document covers the basics of life estimation, failure modes and mechanisms, selection and usage, among other topics. We encourage you to read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Life Estimation ■ Selection and Usage ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

MLCCs can potentially experience either catastrophic insulation breakdown or degradation insulation breakdown. Degradation breakdown tends to be easily controlled and is known to be reversible in most cases by heating above the Curie temperature for 1 to 4 hours. This temporal change is due to the ferroelectricity and volumetric response of the ceramic when cooling from the Curie temperature. This document includes not only the causes of failure for representative capacitors but also the basics of capacitors, how to choose and use them. We encourage you to read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Lifetime Estimation ■ How to Choose and Use ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

To consider the failure modes and failure mechanisms of MF-cap, it is essential to understand the unique self-healing properties of MF-cap. This phenomenon, also known as self-healing (SH) or clearing, is closely related to the failures and lifespan of MF-cap. This document includes not only the typical causes of capacitor failures but also information on selection, usage, and the basics of capacitors. We encourage you to read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Failure Mechanisms ■ Lifespan Estimation ■ Selection and Usage ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

Al-Ecap offers a large capacitance per unit volume and excellent cost performance due to its unique electrodes made from a porous material with a large surface area and a thin dielectric with a high relative permittivity. However, AL-Ecap tends to have a shorter lifespan compared to MF-cap under operating conditions that involve high electrical and thermal stress, leading to faster degradation and failure. This document includes not only the causes of failure for representative capacitors but also the basics of capacitors and lifespan estimation. We encourage you to read it. 【Contents】 ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Lifespan Estimation ■ Selection and Usage ■ Conclusion *For more details, please download the PDF or feel free to contact us.

• Capacitor

There are several failure modes for capacitors, and the frequency of occurrence varies depending on the type of capacitor. Catastrophic failure of a capacitor can result in an open or short circuit. This failure can lead to the explosion of the casing, smoke, fire, damage to other electrical components, and leakage of liquids or gases from inside the capacitor. This document includes information on capacitor failure modes and mechanisms, as well as lifespan estimation, selection, and usage. We encourage you to read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Lifespan Estimation ■ Selection and Usage ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

Failures are classified into catastrophic failures, where functionality is completely lost, and degradation failures, which are defined as failures where characteristics deteriorate and fall outside acceptable ranges. The failure mechanism is the "process leading to failure." In other words, it is the process by which various causes such as electrical, physical, mechanical, and chemical lead to failure. This document also covers the differences between failure modes and failure mechanisms, as well as the basics of capacitors, how to choose and use them. We encourage you to read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Failure Mechanisms ■ Lifetime Estimation ■ How to Choose and Use ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

We would like to introduce "Multilayer Ceramic Capacitors (MLCC)." MLCCs are widely used because they are compact and can achieve high capacitance, making them suitable for surface mounting. They are composed of layers of ceramic dielectric material sandwiched between metal electrodes. This document includes not only representative capacitors but also information on how to choose and use them, as well as failure modes and failure mechanisms. We encourage you to download it and read through it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Failure Mechanisms ■ Lifetime Estimation ■ How to Choose and Use ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

We would like to introduce the "Metal Film Capacitor (MF-cap)." Due to local inhomogeneities and defects in the dielectric film leading to overall failures, there were drawbacks in lifespan characteristics. However, the MF-cap, developed using deposition technology to create an ultra-thin metal deposition film on the film surface, has significantly improved lifespan characteristics and enabled miniaturization. This document includes not only representative capacitors but also the basics of capacitors and lifespan estimation. We encourage you to download it and read through it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Lifespan Estimation ■ Selection and Usage ■ Conclusion *For more details, please download the PDF or feel free to contact us.

• Capacitor

Here is an introduction to "Aluminum Electrolytic Capacitors (Al-Ecap)." Al-Ecap has a structure where a separator soaked with electrolyte is sandwiched between two aluminum foils, rolled up into a cylindrical shape. One of the aluminum foils has a highly roughened surface and is covered with an oxide layer that functions as a dielectric. This document provides detailed information not only about representative capacitors but also about failure modes and mechanisms, selection and usage, etc. Please feel free to download it and read through it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Lifetime Estimation ■ Selection and Usage ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

We would like to introduce the types of representative capacitors. There are structures such as "Aluminum Electrolytic Capacitors (Al-Ecap)" which consist of two aluminum foils sandwiching a separator soaked with electrolyte, "Metalized Film Capacitors (MF-cap)," and "Multilayer Ceramic Capacitors (MLCC)." This document also provides detailed information on the characteristics and structures of each type. Please feel free to download it and read it. [Contents] ■ Introduction ■ Basics of Capacitors ■ Failure Modes and Mechanisms ■ Lifetime Estimation ■ How to Choose and Use ■ Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

The types of capacitors are classified by dielectric materials, and the differences in dielectrics significantly affect capacitor performance, such as capacitance range and voltage rating. Even if the dielectric is the same, the characteristics can vary depending on the type of electrodes and the form of the components. This document includes not only the classification of capacitors but also the differentiation based on capacitance and rated voltage, as well as differentiation based on applications. Please download it and take a look. 【Contents】 ■Introduction ■Basics of Capacitors ■Failure Modes and Failure Mechanisms ■Lifetime Estimation ■Selection and Usage ■Summary *For more details, please download the PDF or feel free to contact us.

• Capacitor

A capacitor is a device that stores electric charge. Electric charge is the electricity possessed by matter or particles, and a capacitor accumulates charge on two opposing electrode plates due to the potential difference V. This document includes not only the basic properties of capacitors but also information on failure modes and mechanisms, selection and usage. Please feel free to download it and give it a read. 【Contents】 ■Introduction ■Basics of Capacitors ■Failure Modes and Mechanisms ■Lifetime Estimation ■Selection and Usage ■Conclusion *For more details, please download the PDF or feel free to contact us.

• Capacitor

This document explains the basic properties, types, and characteristics of capacitors, as well as methods for extending their lifespan, using charts and diagrams. Based on the mechanisms of failure, it introduces how to select and use capacitors. Please download it and take a look. 【Contents (excerpt)】 ■ Failure modes and failure mechanisms (the difference between failure modes and failure mechanisms) ■ Lifetime estimation (basics of lifetime estimation / key points for estimating the lifetime of main capacitors) ■ Selection and usage (design margins and derating / variation in characteristics)

• Capacitor

It is suitable for DC link circuits that require high voltage and high ripple current, such as inverters and power supplies. We have a rich lineup available. 【Features】 ■ Operating temperature range: -40 to +105℃ ■ Rated voltage: 450 to 1,200V.DC (at 85℃) ■ Nominal capacitance: 1 to 80μF ■ RoHS compliant *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

This is a large film capacitor for DC applications that supports high voltage and high ripple current. It is suitable for applications such as large inverters and power supplies that require high voltage and high ripple current. 【Features】 ■ Operating temperature range: -40 to +85℃ ■ Rated voltage: 600 to 2,200V.DC ■ Nominal capacitance: 90 to 5,000μF ■ RoHS compliant *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

We are distributing materials that start with the basics of power electronics and capacitors, and introduce the applications and utilization scenarios of various capacitors. Our capacitors are equipped with features suitable for power electronics, such as large size, high capacity, and high voltage resistance, and they come in a wide variety. 【Overview of the Material】 ■ What is Power Electronics? ■ Capacitors Used in Power Electronics - Capacitors are key devices in power electronics - Requirements for capacitors in power electronics - Multilayer ceramic capacitors - Film capacitors with vapor-deposited electrodes - Aluminum electrolytic capacitors - Aluminum or film? Points for selection ■ Case Studies of Applications (7 selections) - Motor drives - Renewable energy systems - Servo drivers - Switching mode power supplies (SMPS) - Pulse power supplies - Uninterruptible power supplies (UPS) - Traction control systems *The material can be viewed immediately via PDF download. Please feel free to contact us with any inquiries.

• Capacitor

In this document, we explain the concept of impedance as part of the fundamental knowledge of capacitor characteristics. We cover topics such as "What is impedance?", "The impedance of actual capacitors," and "Important elements that constitute impedance (ESR, ESL)." We also explain the characteristics of the ESR of aluminum electrolytic capacitors that use an electrolyte. Please feel free to download and take a look. 【Contents】 ■ What is impedance? ■ The impedance of actual capacitors ■ Important elements that constitute impedance (ESR, ESL) ■ ESR and ESL of aluminum electrolytic capacitors ■ Summary *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

In this document, we explain the basic knowledge of capacitor characteristics, incorporating examples and data. In "Capacitance (Main Text)," we discuss dielectrics, the rules for units and symbols of capacitance, and the range of capacitance covered by capacitors. In "About the Capacitance of Aluminum Electrolytic Capacitors," we introduce the structure of the elements and the changes in capacitance due to temperature, using diagrams and graphs. Please feel free to download and take a look. [Contents (Partial)] ■ Capacitance (Main Text) - What is capacitor capacitance? - About dielectrics - Rules for units and symbols of capacitance - Range of capacitance covered by capacitors - Characteristics and properties of capacitance (things to be careful about) *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

The "ZR2 type" is a board-mounted aluminum electrolytic capacitor that improves the allowable ripple current value by approximately 15% compared to the ZR type, which is designed for high ripple applications. The operating temperature range is -25 to +105°C. The rated voltage is 400, 450V.DC. It features a high heat dissipation structure with a pressure relief valve placed on the product's side, and it utilizes a newly developed high-reliability electrolyte and special anode foil. 【Features】 ■ 105°C - 3,000 hours rated ■ Compliant with RoHS directive ■ Approximately 15% improvement in allowable ripple current value compared to the ZR type, which is designed for high ripple applications ■ High heat dissipation structure with a pressure relief valve placed on the product's side ■ Utilizes a newly developed high-reliability electrolyte and special anode foil *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

This document introduces the basic knowledge of electric double-layer capacitors, which have a simple structure and energy storage principle, and are safer and cleaner compared to other devices that utilize chemical reactions. It explains the principles and features, and discusses sustainable applications and future potential. The overview of electric double-layer capacitors (EDLC) and the principles of their structure and energy storage are detailed with diagrams and images. [Content Overview (Partial)] ■ Overview of Electric Double-Layer Capacitors (EDLC) - EDLC is an old yet new energy device. - EDLC is a device that bridges the gap between capacitors and batteries. ■ Why EDLC Stores Electricity (Structure and Energy Storage Principle) - Basic structure of EDLC and electric double layer. - Principle of energy storage (why EDLC can store a large amount of electrical energy). - EDLC is a physical battery. *For more details, please refer to the PDF document or feel free to contact us.

• Power storage device

AICTech's capacitors apply strict quality control and safety standards in product design and manufacturing. However, it is difficult to achieve zero failures in capacitors with current technology standards. The handbook explains the failure modes, phenomena, causes, and countermeasures of capacitors, illustrated with case studies. [Contents (partial)] ■ How capacitors fail - Explanation of failure modes: open failure, short failure, etc. ■ Phenomena and case studies of failures, factors, and countermeasures (15 selected case studies included!) - Smoke coming from the capacitor - Loss of capacitance - Short-circuiting, etc. For confirmation points regarding countermeasures for these failures, detailed information is provided in the materials. *If you would like a copy of the handbook, please request the materials or view the PDF data available for download.

• Capacitor

The "HU type" is a miniaturized version of the conventional HU3 type, a self-supporting aluminum electrolytic capacitor. The maximum operating temperature is +105°C, and the rated voltage is 200 to 550V DC. 【Features】 ■ 105°C - 2,000 hour product ■ RoHS compliant *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

The "VGLR type" is a screw terminal aluminum electrolytic capacitor that improves the allowable ripple current value by approximately 50% compared to the conventional VGL type. The operating temperature range is -40 to +105°C, and the rated voltage is 350 to 500V.DC. By adopting low ESR technology and newly developed special anode foil, along with a high heat dissipation structure, it is possible to utilize the ripple correction factor based on wind speed conditions. 【Features】 ■ 105°C - 5,000 hours rated ■ Compliant with RoHS Directive ■ High ripple handling product with approximately 50% improved allowable ripple current value compared to conventional types ■ New heat dissipation structure, low ESR technology, and newly developed anode foil adopted *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

You can consult with us for technical advice and purchase Jianghai-made Electric Double Layer Capacitors (EDLC) / Lithium-ion Capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power failures, UPS, and various backup power supplies, leveraging the high input/output characteristics of capacitors. ◆ Cells are provided under the JIANGHAI CAPACITOR brand of our group company, and we can also offer modules designed and produced in-house. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

You can consult with us for technical advice and purchase Jianghai-made electric double-layer capacitors (EDLC) and lithium-ion capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power failures, UPS, and various backup power supplies, leveraging the high input-output characteristics of the capacitors. ◆ Cells are provided under the JIANGHAI CAPACITOR brand of our group company, and we can also offer modules designed and produced in-house. *For more details, please refer to the PDF materials or feel free to contact us.

• Capacitor

You can consult with us for technical advice and purchase Jianghai-made Electric Double Layer Capacitors (EDLC) / Lithium Ion Capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power interruptions, UPS, and various backup power supplies, leveraging the high input/output characteristics of capacitors. ◆ Cells are available under the JIANGHAI CAPACITOR brand from our group company, and we can also provide modules that are designed and produced in-house. *For more details, please refer to the PDF materials or feel free to contact us.

• Capacitor

You can consult and purchase Jianghai-made electric double-layer capacitors (EDLC) and lithium-ion capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power interruptions, UPS, and various backup power supplies, leveraging the high input/output characteristics of the capacitors. ◆ Cells are available under the JIANGHAI CAPACITOR brand from our group company, and we can also provide modules designed and produced in-house. *For more details, please refer to the PDF materials or feel free to contact us.

• Capacitor

AICTech's capacitors apply strict quality control and safety standards in product design and manufacturing. However, it is difficult to achieve zero failures in capacitors with current technological standards. The handbook explains the phenomena and causes of capacitor failures, along with examples of countermeasures, illustrated with diagrams. [Contents (partial)] ■ Symptoms to look for in capacitors ■ How capacitors fail (failure modes and factors) ■ Phenomena and examples of failures, factors and countermeasures (15 selected examples included!) ■ Appendix: Basic knowledge of capacitors *If you would like a copy of the handbook, please request the materials or view the PDF data from the download.

• Capacitor

You can consult with us and purchase Jianghai-made electric double-layer capacitors (EDLC) / lithium-ion capacitors (LIC) through our company. ◆ We offer a wide range of shapes to meet customer requirements, including lead types, board-mounted types, and laminated types. ◆ Ideal for AGVs, momentary power interruptions, UPS, and various backup power supplies, leveraging the high input/output characteristics of the capacitors. ◆ Cells are available under the group company brand JIANGHAI CAPACITOR, and we can also provide modules designed and produced in-house. *For more details, please refer to the PDF materials or feel free to contact us.

• Capacitor

Suitable for applications requiring high voltage and high ripple current, such as large inverters and power supplies. ■ Ideal for high-voltage inverters ■ Specialized for high voltage and high ripple ■ Large sizes available up to a maximum of φ116×345L *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

This is a super compact, high-capacity screw terminal aluminum electrolytic capacitor, ideal for bank applications that require a large amount of energy instantaneously. ◆ The HCGW3 type offers up to 200% higher output compared to conventional VF types. - It is a top-level large-capacity aluminum electrolytic capacitor in the industry. - Utilizing our special anode foil and winding technology, we have achieved high storage capacity. ◆ With the industry's largest dimensions of φ121×283L, it reduces the number of units used. - The HCGWA type supports large capacities up to 400WV and 50,000μF. - By reducing the number of units used, it can lower the costs of associated components, wiring, and assembly. - It is also suitable for applications that require lightweight solutions, such as X-ray equipment for rounds. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

I will introduce the mechanism and function of a capacitor. The circuit symbol representing a capacitor consists of two parallel lines. This indicates that the capacitor is made up of two parallel conductive plates. The larger the surface area of the capacitor's electrode plates and the closer the distance between the two plates, the greater the capacity to store electricity. Additionally, the electrode plates are electrically separated by an insulating material, which gives the capacitor the ability to block direct current while storing electricity (capacitance). These materials are generally referred to as dielectrics. 【Functions of a Capacitor】 ■ Stores charge (electricity) ■ Does not allow direct current to pass, but allows alternating current to pass *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

A capacitor is one of the fundamental and important components in electronic circuits. There is no clear distinction between a capacitor and a condenser; both can physically store electric charge. In English-speaking countries, it is called a capacitor (from "electric capacity = capacity"), but in Japan, it is said to have been referred to as "condenser" (＝condenser) due to its function of compressing (＝condense) electricity. For more details, please refer to the PDF download below. *For more information, please refer to the PDF document or feel free to contact us.

• Capacitor

Here is a case where a sound like "zi" or "pi" was heard from a film capacitor when the power was turned on. Film capacitors have a structure that consists of extremely thin plastic film rolled up. While the electrodes at both ends of the element are fixed, the body part is not fixed, making it prone to vibration. When voltage is applied to the capacitor, the Coulomb force acting between the electrodes can cause the dielectric plastic film to vibrate mechanically, resulting in a humming sound. In particular, if there is distortion in the power supply voltage or if the waveform contains harmonic components, the sound level can be high. [Countermeasures] ■ Continuous vibration sound - It is not a malfunction; it does not affect electrical characteristics or reliability. - Capacitors with long cylindrical or flat-shaped elements tend to produce louder sounds. ■ If the sound level exceeds the acceptable range or if there are sporadic popping sounds - Please use a "sound-dampening product" with a short cylindrical shape. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

The lead wire film capacitor mounted on the substrate was coated with resin. The connection between the capacitor element and the lead wire sparked, causing the capacitor to ignite. The cause was that the coated resin repeatedly expanded and contracted, applying stress to the capacitor. As a result, the connection between the capacitor element and the lead wire experienced stress and delaminated, leading to a spark when voltage was applied, which caused the capacitor to ignite. [Countermeasures] ■ When applying an overcoat, select resin considering the thermal expansion coefficient of the substrate. * For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

When the foil electrode type film capacitor was changed to a vapor-deposited electrode type film capacitor with the same rating, the capacitor failed open. Even with the same rating, the vapor-deposited electrode type is set to have a lower pulse current tolerance than the foil electrode type. This is because the vapor-deposited electrode has a higher resistance and generates more heat than the foil electrode. When a steep pulse current or high-frequency current is applied to the vapor-deposited electrode type, the capacitor heats up, causing the dielectric film to thermally shrink, which damages the junction between the vapor-deposited electrode and the collector electrode (metal spraying), leading to an unstable connection. Ultimately, the connection between the two becomes disconnected and fails open, but when high voltage is applied, sparks may occur, potentially causing a fire. [Countermeasures] ■ Ensure that the actual applied current remains below the allowable value. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

The film capacitor in the power circuit shorted and caught fire. In this case, a film capacitor with a vapor-deposited electrode designed for DC was used in an AC circuit. The effective value of the AC voltage and the DC rated voltage of the capacitor were almost the same. As a result, a voltage exceeding the rated voltage continued to be applied to the capacitor, leading to a short circuit and fire. [Countermeasures] - Change to a film capacitor suitable for AC - Set the rated voltage of the capacitor with an adequate margin, considering AC frequency, voltage waveform, voltage fluctuations, and operating temperature - If the DC voltage contains an AC component, it is necessary to choose a capacitor with a DC rated voltage higher than the peak voltage *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

We would like to introduce a case where a series-connected aluminum electrolytic capacitor short-circuited. When a capacitor with a high leakage current is included in a capacitor series, the voltage balance can be disrupted, causing the voltage to drift above the rated voltage, which may lead to the capacitor short-circuiting. For this reason, it is recommended to connect resistors (voltage divider resistors) in parallel with each individual capacitor when connecting capacitors in series. However, in this case, the leakage resistances of the individual capacitors varied significantly, causing the voltage divider resistors to not function properly. 【Countermeasures】 - To achieve a uniform voltage distribution across the series-connected individual capacitors, increase the rated voltage of the capacitors to reduce the disparity in leakage currents, and review the values of the voltage divider resistors. - Use capacitors from the same manufacturing lot to align the behavior of leakage currents against temperature changes and voltage fluctuations. - This can help stabilize the voltage division. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

We would like to introduce a case where a horizontally mounted screw terminal aluminum electrolytic capacitor failed and the sealing part burst. The failed screw terminal aluminum electrolytic capacitor was mounted horizontally with the pressure relief valve positioned at the "6 o'clock" direction. When a capacitor deteriorates or fails, the temperature of the capacitor element rises rapidly, causing gas to be generated inside. This capacitor uses a filler material to secure the element, and as the element temperature increases, this filler material softens and flows, blocking the pressure relief valve. As a result, the smooth operation of the pressure relief valve was hindered, leading to a crack in the sealing part. [Countermeasures] - Change the mounting method so that the pressure relief valve of the aluminum electrolytic capacitor is positioned at the "12 o'clock" direction. - Adopt a structure that secures the element with ribs instead of using filler material. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor

During the replacement work of an aluminum electrolytic capacitor, when the terminals of the capacitor were connected with metal, a spark occurred, surprising the operator. When the capacitor is discharged, the charge stored in the electrodes disappears instantly, and the voltage between the terminals appears to be zero, but the dipole polarization of the dielectric is maintained. If the capacitor is opened with a short discharge time, the voltage is induced again at the electrodes due to the dipole polarization remaining in the dielectric. In other words, the charge stored in the dielectric seeps out and generates a re-induced voltage at the terminals. A spark occurred because the terminals were short-circuited with a conductor in this state. [Countermeasures] ■ Before handling the capacitor, connect a resistor of about 100Ω to 1kΩ between the terminals of the capacitor to discharge the accumulated charge. *For more details, please refer to the PDF document or feel free to contact us.

• Capacitor