月: 2023年9月

What Is an Emergency Power Source?

An emergency power source is a backup system designed to supply power in situations where the regular power supply is interrupted, such as during power outages, disasters, or system failures. Regulations like JIS, the Fire Service Act, and the Building Standards Act define the requirements for emergency power sources in specific applications, such as lifts and fire sprinkler systems.

Uses of Emergency Power Sources

Emergency power sources are crucial in various settings, serving distinct purposes:

1. Hospitals and Medical Facilities

In hospitals, emergency power is vital for maintaining life-supporting medical devices during power failures. Hospital outlets are often color-coded according to JIS standards to distinguish between different types of emergency power sources. Red outlets provide general emergency power, activating within 40 seconds and operating for over 10 hours. Special emergency outlets start within 10 seconds, and green outlets, representing uninterruptible sources, activate immediately via UPS systems.

2. Households

Households may also have emergency power sources for disaster preparedness, using lithium-ion batteries, diesel generators, or propane gas generators. Propane gas generators, for instance, can provide electricity for around 74 hours using 50 kg of propane, aiding in various disaster-related needs.

3. Commercial and Office Buildings

Commercial and office buildings use emergency power to maintain critical functions like lifts and security systems during outages, ensuring business continuity.

Principles of Emergency Power Sources

Emergency power systems typically include storage batteries, generators, and automatic switching devices:

1. Storage Batteries

Storage batteries hold electrical energy in chemical form, ready to be converted back to power during outages, ensuring continuity of critical functions.

2. Generators

Generators convert fuel into rotational energy and then into electrical power, automatically providing power during failures. They are suitable for long-duration power supply needs and larger facilities.

3. Automatic Switching Devices

Automatic switching devices seamlessly transition from regular to emergency power supply in the event of a power loss, and vice versa, when regular power is restored.

How to Select an Emergency Power Source

Selecting the right emergency power source involves considering power requirements, operational duration, and switching speed, all within budgetary constraints:

1. Power Requirements

Assess the power capacity needed to operate essential equipment and systems during emergencies. Ensure the supply voltage matches that of the regular power supply.

2. Continuous Operation Time

Determine the required continuous operation time and accordingly plan for the fuel tank and storage battery capacities. For extended outages, additional fuel storage might be necessary.

3. Switching Speed

Consider the switchover speed, especially for backing up critical telecommunications equipment. Using storage batteries and DC power supplies can minimize outage times.

What Is a Non-contact Tachometer?

A non-contact tachometer is a device used to measure the rotational speed of an object without any physical contact. Unlike traditional tachometers that require direct contact with the rotating shaft, non-contact tachometers ensure non-destructive measurement, eliminating the risk of damage to the object being measured.

These devices typically employ optical methods or magnetic sensors to measure high rotational speeds, providing accurate results even at high velocities. The lack of physical contact also reduces wear and tear, enhancing the sensor’s lifespan and preventing damage to the rotating shaft and the tachometer itself.

Uses of Non-contact Tachometers

Non-contact tachometers find applications across various industries, particularly in monitoring the rotation of motors and their load devices.

1. The Automotive Industry

In the automotive sector, these tachometers are vital for monitoring and controlling vehicle components, measuring engine speed, and rotational speeds of motors and pumps to ensure optimal performance.

2. Energy Industry

In the energy sector, non-contact tachometers are crucial for monitoring machinery like wind and hydro turbines, aiding in efficiency optimization and early problem detection.

3. Sports

These devices also serve in sports performance analysis and training, measuring the wheel rotation speed of sports cars and bicycles to optimize motion and performance.

Principle of Non-contact Tachometer

Non-contact tachometers operate based on various principles, depending on the technology used. Here are some common methods:

1. Optical Principle

Optical non-contact tachometers use a laser beam or light source to measure rotational speed. The light is directed onto the object’s surface, and the reflected light, whose phase and frequency change with the object’s speed, is detected to determine the rotational speed.

2. Magnetic Principle

Magnetic sensor-based non-contact tachometers detect the movement of a magnet attached to the rotating object. The sensor picks up changes in the magnetic field as the object rotates, allowing for the measurement of rotational speed.

3. Acoustic Principle

Acoustic non-contact tachometers use sound waves. Sound waves are emitted towards the object, and the reflected sound, which changes frequency and phase with the object’s rotation speed, is analyzed to measure speed.

4. Electromagnetic Wave Principle

This type of tachometer emits electromagnetic waves onto a rotating object and analyzes the reflected and scattered waves. The changes in phase and frequency of these waves, correlating with the rotational speed, are used for measurement, often incorporating microwave or radar technologies.

How to Choose a Non-contact Tachometer

Selecting a non-contact tachometer requires careful consideration of application range, measurement requirements, and the measurement environment, balancing performance with cost.

1. Application Range

Determine the purpose and application range of the tachometer. For machine monitoring or control, stationary types are preferred, while portable types are better suited for manual operation during inspections.

2. Measurement Requirements

Consider the range of rotational speeds, accuracy requirements, and the size and shape of the object being measured. Products with a broad high-speed range are ideal for high-speed applications, while compact models are preferable for limited spaces.

3. Operating Environment

The measurement environment is crucial. Ensure the chosen tachometer is durable enough to withstand specific conditions, such as high temperatures or corrosive environments.

What Is a Dew Point Meter?

A dew point meter is a device used to measure atmospheric humidity, specifically indicating the temperature at which water vapor condenses into droplets or frost. These meters are crucial for assessing the supersaturation of water vapor in the air and the risk of condensation, combining humidity and temperature data.

Commonly employing the cooled mirror method, dew point meters accurately determine the condensation point of water vapor. They find extensive use across various industries and applications for warning and controlling changes in humidity and potential condensation.

Uses of Dew Point Meters Include

1. Humidity Control

Dew point meters play a vital role in measuring humidity and monitoring condensation at specific humidity levels. They are essential in humidity control within buildings and industrial processes, where condensation can lead to issues like mold and corrosion.

2. Meteorological Observations

For weather forecasting, meteorologists use dew point meters to monitor atmospheric humidity and temperature. This aids in predicting precipitation and the likelihood of fog, frost, and freezing conditions.

3. Fridge and Freezer Control

Monitoring humidity in fridges and freezers is another application of dew point meters, ensuring optimal storage conditions for food and medicines and preventing deterioration or loss of quality.

4. Industrial Processes

In various manufacturing and quality control processes, particularly where specific humidity conditions are critical (like in painting, drying, and plastic molding), dew point meters are indispensable for humidity control.

5. Environmental Monitoring

These meters are also used for environmental protection and quality control, monitoring air humidity. Fluctuations in humidity can impact moisture levels in the air and pollutant diffusion, making dew point meters essential for environmental monitoring.

Principle of Dew Point Meters

Dew point meters, designed to measure air moisture content, primarily utilize either the capacitance or the cooled mirror method for measurement.

The capacitance method, commonly used in portable models, is simpler to operate. In contrast, the cooled mirror method, favored for its accuracy, is the go-to choice in applications where precision is paramount.

1. Capacitance Type

The capacitance-type dew point meter uses electrical conductivity to detect moisture. It contains a thin sensor with a special metal coating that changes its resistance value with the amount of moisture present, thus measuring the moisture content.

2. Mirror-Cooled Type

The mirror-cooled method involves spraying the gas onto a mirror inside the meter. Cooling and heating cycles on the mirror cause and then eliminate condensation. This method, though time-consuming, allows for highly accurate dew point measurements by finding the optimal balance through repeated operations.

How to Choose a Dew Point Meter

1. Intended Use

Identifying the specific application of the dew point meter is crucial. Requirements vary depending on the usage context, such as construction, industrial process control, weather observation, or environmental monitoring.

2. Measuring Range and Accuracy

It’s important to select a dew point meter with a suitable measuring range and high accuracy, tailored to the specific application. While higher accuracy and broader ranges can be more costly, they are vital for certain applications, making budget considerations an important factor.

3. Data Logging and Communication

If data management, analysis, and sharing are important, ensure that the dew point meter supports data logging and communication features. For real-time monitoring and data management, select a meter with appropriate capabilities.

4. Durability and Maintenance

Choose a durable dew point meter that promises long-term accuracy. Also, consider the ease of maintenance and calibration, opting for a model that simplifies these processes for sustained use.

What Is an Electromagnetic Wave Absorbing Sheet?

An electromagnetic wave absorbing sheet is a component used in electronic equipment that generates electromagnetic waves or may malfunction due to electromagnetic waves.

EMC (electrode compatibility) measures for electronic equipment include EMI (Electro Magnetic Interference), which is a measure for electromagnetic noise generation, and EMS (Electro Magnetic Susceptibility), which is a measure for the receiving side. The International Electrotechnical Commission (IEC) standards and the Electrical Appliance and Material Safety Law define the methods used.

Electromagnetic wave absorbing sheets are a typical component used for such measures. In recent years, as CPU speeds have increased, the frequency band of electromagnetic waves has shifted to higher frequencies, making noise countermeasures more difficult. By attaching electromagnetic wave absorbing sheets near noise sources, noise in the vicinity can be absorbed and suppressed.

Composites of magnetic materials and rubber and thin plastic laminates are available as electromagnetic wave absorbing sheets, which are easy to cut and affix, inexpensive and lightweight.

Uses of Electromagnetic Wave Absorbing Sheets

The uses of electromagnetic wave absorbing sheets are generally not well known, but they are used in a very wide range of fields. Typical applications are as follows.

1. Electronic Equipment Applications

Electromagnetic wave absorbing sheets are used in equipment with semiconductor substrates inside, such as smartphones and household appliances. By attaching electromagnetic wave absorbing sheets to the inside of housings and to circuit boards, it is possible to reduce the generation of radiated noise, resonance and internal reflections in the equipment.

2. Applications for Countermeasures Against Communication

interference
Electromagnetic wave absorbing sheets are used to reduce noise in aircraft and ship radios, which use electromagnetic waves with a frequency of 30 MHz or lower. Electromagnetic wave absorbing sheets are also used to prevent telephone interference in mobile phones and televisions, which are indispensable in daily life.

3. Automotive Applications

In recent years, automobiles have been equipped with numerous sensors, including anti-collision radar. Radar uses millimetre waves, and electromagnetic wave absorbing sheets are used as a countermeasure against electromagnetic interference and noise.

Principle of Electromagnetic Wave Absorbing Sheets

Electromagnetic wave absorbing sheets convert electrical energy into thermal energy by having the electromagnetic waves absorbed by the magnetic material compounded in the sheet. Different types of magnetic materials are used depending on the absorption band of the electromagnetic waves, for example, to prevent noise in satellite communications, materials that can selectively absorb the frequency bands that are practical there are used.

In recent years, electromagnetic wave absorbing sheets made of plastic or non-woven fabrics, which do not use magnetic materials, have also been distributed. The former type absorbs electromagnetic wave absorbing sheets by generating polarisation through the lamination of plastic sheets with different dielectric constants. The latter uses non-woven fabrics with special surface treatment to convert noise into heat through resistive losses.

Types of Electromagnetic Wave Absorbing Sheets

There are various types of electromagnetic wave absorbing sheets in circulation, depending on the materials they are made of. Typical types are as follows.

1. Electromagnetic Wave Absorbing Rubber Sheets

These sheets are a mixture of magnetic material and rubber. They have excellent flexibility and insulation properties characteristic of rubber and are easy to process. They also have good corrosion resistance and are suitable for harsh operating conditions such as humid environments. Thicknesses range from 0.25 mm for thin sheets to 4 mm for thicker ones.

2. Electromagnetic Wave Absorbing Plastic Sheets

This product is made of laminated plastic sheets moulded from polyester resin. As they do not contain magnetic materials, costs can be kept low, and they have the advantage of being lightweight due to their thin thickness. Transparent products are also available and can be used for adherends that require light transmission, such as windows.

3 Electromagnetic Wave-Absorbing Non-woven Fabrics

Like plastic sheets, these are environmentally friendly products that do not use magnetic materials. The thickness can be reduced to 50 µm at its thinnest point, and its flexibility allows it to follow the unevenness of semiconductor substrates.

What Is an Electric Torque Spanner?

An electric torque spanner is a tool that uses an electric power source, such as a motor, to fasten bolts and nuts. It is sometimes also referred to as a ‘nutrunner’.

Electric torque spanners can tighten bolts and nuts to a specified torque at high speed by combining the functions of an electric socket spanner and a torque spanner. This tool significantly improves the efficiency of bolt and nut fastening operations.

There are electric torque spanners that perform from temporary tightening to final target conditions (tightening torque and angle of rotation), as well as models that allow for temporary electric tightening and final manual tightening. The latter are known as semi-automatic electric torque spanners, as they involve manual intervention.

Uses of Electric Torque Spanners

Electric torque spanners are used in fastening tasks involving a large number of bolts and nuts, where speed and high torque are crucial. For instance, the construction of large steel-framed buildings necessitates fastening numerous bolts.

These tools not only enhance work efficiency but also contribute to shorter construction periods. In high-altitude environments, such as in the construction of transmission line towers and wind turbines, electric torque spanners offer safety advantages, preventing accidents that can occur if an operator loses balance.

Designed for safety and efficiency, electric torque spanners include support mechanisms to counteract reaction forces and a design that minimizes operator stress. For high-torque applications, such as tightening 10-hole wheel nuts on large vehicles to the ISO standard of 600 N-m, electric torque spanners are the tool of choice.

For a three-axle vehicle, this means tightening 60 nuts across six wheels. Electric torque spanners excel in tasks requiring numerous high-torque fastenings.

Principle of Electric Torque Spanners

Electric torque spanners operate using an electric motor. They incorporate a reduction gear mechanism, often a planetary gearbox, enabling small motors to achieve high torques. Clutch mechanisms are used to reach a set torque, and angle detection mechanisms allow for precise angle-controlled operations.

Features of Electric Torque Spanners

Unlike impact spanners, electric torque spanners produce minimal noise, making them suitable for night-time or residential area use. Their low noise and vibration levels also reduce the risk of occupational accidents. These spanners not only lessen physical strain on operators but also lower the risk of conditions like hand-arm vibration syndrome and carpal tunnel syndrome, as well as noise-induced hearing loss.

Some models can connect to computers for managing and recording tightening data, such as ‘which bolts and nuts were tightened and at what torque’. This capability aids in preventing accidents due to untightened bolts and enables verification of work procedures.

While highly advantageous, these models inevitably increase in weight, especially those designed for large torques. When using larger electric torque spanners, the use of a spanner hanger with a damper is necessary for support, which can limit workspace and storage size.

Other Information on Electric Torque Spanners

1. Small Electric Torque Spanner

Small electric torque spanners, often handheld and battery-rechargeable, offer the advantage of cordless operation, allowing unrestricted work movement and placement.

These models can manage torque and maintain wireless communication capabilities for data transmission and control signal reception. This feature is also available in corded models, enabling centralized data management in factory settings.

2. Torque Management With Electric Torque Spanners

Electric torque spanners monitor torque and changes in angle and speed during tightening. Work records can be stored in the tool itself or wirelessly transmitted to a host for assembly result data management. These functions enable accurate determination of whether bolts are properly tightened. Issues such as diagonal tightening, and omitted or double washer insertions can be identified from torque data.

Advanced models can detect the spanner’s posture and position, assessing the fastening hole’s location to ensure correct bolt or nut tightening. They can also automatically adjust tightening torque based on the bolt or nut specifications and working position.

What Is an Electromagnetic Coating Thickness Gauge?

An electromagnetic coating thickness gauge is a device that measures the thickness of a thin film using the principle of electromagnetic induction.

The thickness can be measured by placing a coil close to the measurement area and measuring minute inductive electromotive forces. It measures the thickness of thin films and coatings that cannot be measured with calipers, etc. There are other types of film thickness gauges, such as eddy current, ultrasonic and reflectance spectroscopy, and it is important to select the right one depending on the object to be measured.

While electromagnetic coating thickness gauges can instantly and accurately measure thickness, they have the disadvantage that they cannot measure well if the thin film is magnetic.

Uses of Electromagnetic Coating Thickness Gauges

1. Metal Industry

Electromagnetic coating thickness gauges are widely used in the metal product manufacturing industry. The measurement of metal film thickness enables product quality control and optimisation of the manufacturing process. For example, in the automotive industry, to ensure paint uniformity and durability.

2. The Construction Industry

In the building industry, electromagnetic coating thickness gauges are used to measure the thickness of coatings and paints applied to concrete and steel surfaces. This ensures the durability and visual quality of buildings.

3. Corrosion Monitoring

Corrosion monitoring is used to monitor the corrosion state of metal products and structures. As the film thickness decreases as corrosion progresses, regular measurements enable the progress of corrosion to be monitored and the necessary protective measures to be taken.

4. Electronics Industry

Electromagnetic coating thickness gauges are used to measure the film thickness on the surface of minute components such as electronic components and printed circuit boards. This is essential to ensure the performance and reliability of components.

5. Chemical Industry

In chemical processes, electromagnetic coating thickness gauges are used to control and monitor the film thickness of chemical and coating materials. They contribute to improved product quality and process optimisation.

6. Aerospace Industry

Uniformity of film thickness and accurate dimensions are important for aircraft and space equipment components. Electromagnetic coating thickness gauges are an essential tool in the manufacture and maintenance of these components.

Principle of Electromagnetic Coating Thickness Gauge

The structure consists of a probe containing an electromagnet, which is brought into contact with the surface to be measured. When an electric current is applied to the electromagnet, electromagnetic induction occurs, attracting the magnetic material behind the thin film. The voltage of the coil changes according to the distance between the electromagnet and the magnetic material, and this is used to measure the film thickness.

Like calipers, it does not need to be clamped from both sides and can measure minute thicknesses that cannot be measured by eye. In addition, electromagnetic coating thickness gauges can instantly and accurately measure thickness, and are easy to operate and can be handled by anyone.

Thickness can only be measured when the substrate is magnetic, such as a metal, and the object to be measured is non-magnetic. Examples include non-magnetic metal plating, paint and resin coatings. On the other hand, if the film thickness is under a non-magnetic object or if the object has an uneven surface, it cannot be measured accurately because the electromagnet must be in close contact with the surface.

How to Select an Electromagnetic Coating Thickness Gauge

1. Intended Use

First of all, it is necessary to clarify for which application the electromagnetic coating thickness gauge is to be used. There are different types to suit different applications, e.g. for measuring the thickness of metal coatings, measuring the thickness of coatings, monitoring corrosion, etc. 2.

2. Accuracy and Resolution

If measurement accuracy is important, it is essential to choose a high-precision electromagnetic coating thickness gauge. It is also important to take resolution into account. The required accuracy and resolution depend on the intended use and application, so the application must first be determined.

3. The Type of Material

It is important to select the right electromagnetic coating thickness gauge for the material being measured. The suitable electromagnetic coating thickness gauge depends on the material of the object, e.g. metallic, non-metallic or coated materials.

4. Measuring Range

Consider the range of coating thicknesses to be measured and whether the range can be covered. There are various options available, ranging from wide to narrow ranges. If the range cannot be foreseen in advance, electromagnetic coating thickness gauges that can measure as wide a range as possible should also be considered.

5. Ease of Operation

The ease of use of electromagnetic coating thickness gauges is also a factor to be considered. An intuitive interface and easy-to-use software will help to ensure efficient measurement operations. As detailed work may be required, it is important to take into account the time required for operation.

6. Durability and Maintenance

To maintain stable performance over a long period of time, it is necessary to select durable products. Regular maintenance and calibration are also important, so it must be ensured that they can be easily performed.

What Is an Electromagnetic Counter?

An electromagnetic counter is a device that counts by the operation of an electromagnet built into the electromagnetic counter, which is activated by the pulse wave of an electrical signal.

It is connected to the actual circuit and operates only with external power, as the fluctuating value of the electrical signal is changed to a mechanical force by the magnets and counted. Electromagnetic counters can be classified into two categories: preset counters, which act as switches to operate the device according to the counted value, and total counters, which output only the counted value.

Uses of Electromagnetic Counters

Electromagnetic counters are mainly used in production plants for a variety of products. When selecting an electromagnetic counter, it is necessary to consider factors such as counting accuracy, the amount of current and voltage in the circuit to be connected, ease of maintenance, connectivity, vibration resistance and dust resistance.

1. Electrical Circuit Measurement

Used as ammeters and voltmeters, they measure the current and voltage of electrical circuits. This enables the management of the electricity supply network and the design and troubleshooting of electronic equipment.

2. Electricity Metering

Also used as electricity meters, they measure electricity consumption in households and industry, helping to regulate the electricity supply and calculate tariffs.

3. Geomagnetic Measurement

Used as a magnetometer, it measures fluctuations in the earth’s magnetic field. This is important for studying geomagnetic activity and calibrating compasses that use geomagnetic orientation.

4. Metal Detection

Used as a metal detector to detect buried metal objects (e.g. currency, weapons, underground pipes, etc.). Used for security checks and searches for valuables.

5. Non-destructive Testing

Used for non-destructive testing to detect defects and anomalies inside materials. For example, it is used to assess the quality of welds and to measure the density of materials.

6. Medical Equipment

In the medical sector, the electromagnetic counter principle is used in diagnostic imaging devices such as MRI (magnetic resonance imaging) and CT scans (computed tomography). These devices help to visualise tissues and organs in the body in detail.

Principle of Electromagnetic Counters

Electromagnetic counters consist of wiring for connection to a circuit, a coil, an electromagnet and a counter whose value fluctuates as the electromagnet moves. In the case of preset counters, a device is included to transmit the counting values to other devices.

Electromagnetic counters usually generate a magnetic field around the coil by generating an external current pulse, which is then passed through the coil. The magnetic field of the magnetic field affects a nearby metallic object and induces a current in the metallic object. This induced current is generated by the metallic object and its magnitude depends on the nature and position of the object.

How to Choose an Electromagnetic Counter

1. Intended Use

First of all, it is important to clarify for which application the electromagnetic counter is to be used. There are suitable models for current measurement, voltage measurement, geomagnetic measurement, metal detection, etc.

2. Measuring Range and Accuracy

The measuring range and accuracy must be chosen to suit the specific application. If high-precision measurements are required, choose a counter with high accuracy. If a wide range of currents or voltages are to be measured, counters with a wide measuring range are suitable.

However, it is important to strike a balance, as selecting counters with excessively high accuracy or wide ranges can lead to high costs.

3. Interfaces and Data Acquisition

If data acquisition or recording is required, it should be checked whether there is an interface (e.g. analogue output, digital output, RS-232C, USB, Ethernet) or data logging function (i.e. the counter records the measured data at regular intervals for later analysis).

4. Calibration and Maintenance

Electromagnetic counters require regular calibration and maintenance. Check the calibration procedure and ease of maintenance of the chosen model. Particularly with regard to maintenance, this includes regular inspection, cleaning and replacement of parts to prevent counter components from deteriorating or wearing out.

If the counter is used under specific environmental conditions (e.g. high temperature, high humidity, corrosive environments, etc.), maintenance measures must be adapted to these conditions.

What Is a Power Supply Board?

A power supply board is responsible for supplying the voltage and current that meets the specifications to the circuits that make up the equipment.

Generally, the power supply circuit is designed to take 100 V AC commercial power as input and output the DC voltage required by the internal circuits. The DC voltage required by the internal circuits can be aggregated to between 3.3 V and 48 V, depending on the equipment. Furthermore, the required current values can also be aggregated.

The value of utilising a power supply board with a power supply circuit made for general purpose use as a finished component, rather than optimising and designing it for individual devices in-house, is significant.

Costs can be reduced by narrowing down the specifications to a few types of power supply board and producing them in large quantities. The reason for this is that engineers specialising in power supply circuit design can design high-performance designs.

Uses of Power Supply Boards

Power supply boards are used in a wide range of equipment, including industrial equipment, information processing equipment such as computers and servers, home appliances such as televisions and refrigerators, and audio-visual equipment such as recorders and audio components.

The installation space allowed for power supply circuits is becoming increasingly restricted due to the increasing sophistication and performance of various devices and the miniaturisation of equipment, resulting in the need for miniaturisation, high performance and high efficiency.

The need for dedicated power supply boards is increasing for these reasons, in addition to the potential cost savings compared to in-house design.

Principle of Power Supply Boards

Power supply boards include AC/DC power supply boards, which convert AC voltage to DC voltage, and DC/DC power supply boards, which boost or step down DC voltage.

1. AC/DC Power Supply Boards

Generally takes 100 V AC commercial power as input and outputs the specific DC voltage required by the equipment’s internal circuitry.

2, DC/DC Power Supply Board

After being converted to DC voltage in the equipment, the output is further boosted or stepped down to the specified voltage required by the internal circuits.

 

In addition to simply converting AC to DC or converting DC voltage, there are many power supply boards with various built-in protective functions, such as overcurrent protection circuits and overvoltage protection circuits to deter excessive current from flowing into the internal circuits, and overcurrent protection circuits to deter heating due to the amount of current flowing into the circuit. Many power supply boards are available.

In addition, power supply circuits can sometimes cause heat generation and ignition due to incorrect use of the equipment. As standards are strictly defined by various safety standards, power supply boards are generally compliant with various safety standards.

Other Information on Power Supply Boards

1. Benefits of Power Supply Boards

One advantage of power supply boards is that they reduce EMI (Electro Magnetic Interference) noise. The DC-DC converter IC, which is a major noise source, and the coils and capacitors are wired short, and the optimised structure reduces noise.

Noise emitted by DC-DC converters is amplified by the wiring acting like an antenna, so shortening the wiring is an effective noise suppression measure.

2. Types of Dc-Dc Converter Operation

There are two types of operation among DC-DC converters.

Linear Regulators.
This is a method of obtaining an output voltage by dividing the input voltage between the loads. The voltage divider ratio can be changed by using a transistor or similar between the loads and treating it as a variable resistor.

This method has the disadvantage of low energy conversion efficiency, as the power consumed by the voltage dividing resistor is lost. On the other hand, the advantages include low electromagnetic noise.

Switching Regulator
This is a method whereby a pulse wave is created from the input voltage by switching elements on and off, and smoothed at the output. The voltage can be controlled by changing the on/off ratio.

It has high energy conversion efficiency, but has the disadvantage of high noise generated during switching.

What Is a Power Supply Board?

A power supply board is a component responsible for providing the specific voltage and current required by the circuits within a device. It ensures that the electrical specifications are met accurately for the equipment’s proper functioning.

Typically, a power supply circuit is designed to accept 100 V AC commercial power and convert it into the DC voltage needed by the device’s internal circuits. The required DC voltage often ranges from 3.3 V to 48 V, varying with the equipment. Additionally, the power supply board aggregates the necessary current values.

Using a general-purpose power supply board as a finished component, instead of designing a customized one for each device, offers significant value. This approach allows cost reduction by standardizing a few power supply board types and manufacturing them in bulk, leveraging the expertise of engineers specializing in power supply circuit design.

Uses of Power Supply Boards

Power supply boards are integral to various equipment types, including industrial machinery, information processing devices like computers and servers, home appliances such as TVs and refrigerators, and audio-visual components like recorders and audio systems.

As devices become more advanced and equipment miniaturizes, the space allocated for power supply circuits is increasingly limited, demanding compact, high-performance, and efficient power supply boards. The growing need for specialized power supply boards, coupled with the cost benefits over in-house design, is evident.

Principle of Power Supply Boards

Power supply boards are categorized into AC/DC and DC/DC types, converting AC to DC voltage, and modifying DC voltage levels, respectively.

1. AC/DC Power Supply Boards

These boards typically convert 100 V AC commercial power into the specific DC voltage required by a device’s internal circuits.

2. DC/DC Power Supply Boards

These boards adjust the DC voltage obtained from the equipment, either increasing (boosting) or decreasing (stepping down) it to match the requirements of the internal circuits.

In addition to voltage conversion, many power supply boards incorporate protective features such as overcurrent and overvoltage protection circuits. These safeguards prevent excessive current flow and overheating in the circuits. Most power supply boards comply with various safety standards to prevent hazards like heat generation and ignition due to incorrect equipment use.

Other Information on Power Supply Boards

1. Benefits of Power Supply Boards

A significant benefit of power supply boards is their ability to reduce EMI (Electromagnetic Interference) noise. This is achieved by short wiring of the noise-prone DC-DC converter IC, coils, and capacitors, and an optimized structure that effectively minimizes noise. Short wiring is crucial as it prevents the amplification of noise that occurs when wiring acts as an antenna.

2. Types of DC-DC Converter Operation

DC-DC converters operate in two main modes:

Linear Regulators:
These regulators achieve the desired output voltage by dividing the input voltage across loads. The division ratio is modifiable using a transistor or similar component as a variable resistor. While they are low in energy conversion efficiency and lose power through the voltage dividing resistor, linear regulators have the advantage of emitting low electromagnetic noise.

Switching Regulators:
Switching regulators generate a pulse wave from the input voltage by toggling switch elements on and off, which is then smoothed at the output. The voltage is controlled by altering the on/off ratio. These regulators are highly efficient in energy conversion but produce higher noise during the switching process.

What Is a Watt-Hour Meter?

A watt-hour meter is an electrical device used to measure the amount of electricity consumed.

By measuring the electricity usage in factories and residences, it helps calculate individual customers’ electricity rates. A watt-hour meter consists of an ammeter and a voltmeter, whose readings are multiplied to calculate the electricity consumed.

Watt-hour meters objectively measure electricity consumption, thus preventing billing disputes and fraud between consumers and electricity suppliers. Their use increases the transparency and reliability of electricity billing.

They also enable regular data collection, aiding in identifying electricity usage patterns and trends. This facilitates monitoring and management of electricity consumption, enabling efficient energy management and demand forecasting.

Uses of Watt-Hour Meters

Watt-hour meters are used in various settings where electricity is consumed. They are commonly installed in the following locations:

1. General Households

In general households, watt-hour meters measure electricity usage. They help monitor household electricity consumption and assist in managing electricity bills. They are also used with private power generation systems, such as solar panels, to measure the electricity generated and consumed.

2. Commercial and Office Buildings

In commercial and office buildings, these meters are used for energy management and monitoring electricity usage. They serve as indicators for implementing energy conservation measures.

3. Manufacturing Industry

In the manufacturing industry, watt-hour meters are used to monitor the electricity consumption of production equipment. This aids in improving efficiency and energy management, reducing production costs and environmental impact.

Principle of Watt-Hour Meters

All watt-hour meters calculate electricity usage based on current and voltage measurements. The current is measured by a current transformer or similar device within the meter, while the voltage is measured by an instrument transformer or similar. These sensors detect fluctuations in current and voltage and output analog signals.

The meters accumulate data on the measured currents and voltages at regular intervals. Current and voltage are measured as instantaneous values but can be integrated over time to determine total electricity consumption.

Types of Watt-Hour Meters

There are several types of watt-hour meters, including:

1. Induction Disc Type

This type of meter consists of a current coil, a voltage coil, an aluminum disc, and a measuring device. Electromagnetic induction generated by the current coil connected to the load causes the aluminum disc to rotate for measurement.

2. Electronic Type

The electronic watt-hour meter uses an internal electronic circuit to measure current and voltage and calculate electricity usage. Compared to the induction disc type, it has fewer mechanical components and thus a lower risk of breakdowns, allowing for longer operation without issues.

3. Smart Meters

Smart meters are advanced watt-hour meters with enhanced functions and communication capabilities. Equipped with communication features, they can transmit electricity data remotely. The digital display of electricity usage can promote energy conservation awareness. Smart meters, integral to Japan’s policy of widespread adoption, do not incur meter replacement costs for households. However, concerns about privacy and the potential inference of personal information from electricity data have been raised.

Other Information on Watt-Hour Meters

Expiry Date of Watt-Hour Meters

Watt-hour meters used in trade have an expiry date set by the Measurement Act: 10 years for stand-alone meters and 7 or 5 years for transformer-connected meters. Trading with expired meters incurs penalties under the Measurement Act. Utility companies, responsible for meter installation, typically attach a sticker indicating the expiry date to the meter.