投稿者: Fujiwara

What Is a Wireless Control Relay?

A wireless control relay is a relay device that receives electrical signals and outputs digital signals to control machinery, using wireless communication methods such as Bluetooth.

Control relays receive external electrical signals and perform tasks like turning electrical circuits on/off or switching them. They relay input signals from sensors or push buttons to other devices. Communication methods vary by product, including Wi-Fi, Bluetooth, and sub-GHz band wireless. These relays are used in various industrial scenarios where wired installation is difficult or in coordination with wireless sensors.

Uses of Wireless Control Relays

Overview

Wireless control relays are used to receive signals wirelessly from sensors and push-button switches and control other devices or processes wirelessly. Specific applications include:

• Controlling industrial processes in conjunction with wireless temperature or pressure sensors
• Smart home automation
• Eliminating wiring in manufacturing and conveyance processes in factories

Applications in Manufacturing

In manufacturing, wireless control relays are used with sensors and switches in the following ways:

• Efficient transmission of trouble alerts
• Efficient reporting of task completion
• Switching the direction of conveyor belts
• Wire-free layouts allowing flexible layout changes
• Remote operation of forklift communication and shutter control
• Counting inspection results and distinguishing between good and defective products
• Activating AGVs (Automated Guided Vehicles) for parts transport
• Indicating vehicle entry and exit

Principle of Wireless Control Relays

Overview and Wireless Communication

A relay is a component that receives external electrical signals and controls the on/off or switching of electrical circuits. Wireless control relays use various wireless communication methods, such as Wi-Fi, low-power radio, Lora, LoRaWAN, and Bluetooth, for communication with sensors and target devices. The suitable data communication method is selected based on the product and application. For example, LoRaWAN offers excellent reception sensitivity and resistance to radio interference, enabling communication distances of over 10 km in ideal environments, making it suitable for wide-area operations.

Wireless control relays, like traditional relays, come in two types: mechanical contact relays and solid-state relays.

Mechanical Contact Relays

Mechanical contact relays operate by mechanically moving contacts to output a contact signal. They are composed of components like electromagnetic coils and contacts and are also known as electromechanical relays due to their operating principle.

When an input voltage signal is received, the internal electromagnetic coil is energized, acting as an electromagnet and moving the movable contact with the movable iron piece. The movable contact touches or separates from the fixed contact, outputting an electrical contact signal.

Solid-State Relays

Solid-state relays have no mechanical moving parts like contact relays and are composed of semiconductors and electronic components like triacs and MOSFETs. They electronically switch signals or currents/voltages on and off using these electronic circuits.

Types of Wireless Control Relays

Wireless control relays come in various types. In addition to the operational mechanisms of contact and solid-state relays, there are different types of contact configurations and output methods. The types of contacts include:

• Form A (Normally Open) Contact: Activated by the input signal
• Form B (Normally Closed) Contact: Deactivated by the input signal
• Form C (Transfer) Contact: Combines Form A and Form B, with each operating inversely to the input signal

Functionally, there are products designed to work with wireless pressure sensors or temperature sensors, products with integrated push-button switches, and products intended for smart home applications. The hardware aspects, such as operating temperature, vary by product. Products with an IP54 waterproof rating, for example, can be used in wet environments or outdoors.

What Is a Wireless Pressure Sensor?

A wireless pressure sensor measures pressures, such as gauge pressure, in factories and plants without needing wired connections for power or communication.

In many industrial settings, it is essential to measure and manage the pressure of gases and liquids, including gauge pressure, sealed gauge pressure, and differential pressure. Traditional wired pressure sensors require long power cables and can have installation limitations. Wireless pressure sensors eliminate these restrictions, allowing for installation in desired locations. The power sources are mainly divided into battery-powered and self-powered types. Additionally, some products are used in educational settings for scientific experiments.

Uses of Wireless Pressure Sensors

Wireless pressure sensors are used in various industrial applications, including power plants, chemical plants, oil refineries, and food processing facilities.

Many industrial processes involve the use of pressurized gases or pressurized containers. Monitoring pressure is crucial as pressurized leaks or container expansions can disrupt the safe operation of manufacturing processes. Primary uses include:

• Online and remote gauge monitoring
• Valve leakage monitoring
• Monitoring pipeline and filter blockages
• Measuring gas and liquid flow rates
• Tank level measurement
• Monitoring gas and liquid filters
• Process control in factories

Wireless pressure sensors are also used in educational settings for various physics and chemistry experiments, such as Boyle’s law and measuring pressure inside balloons.

Principle of Wireless Pressure Sensors

Measurement Mechanism

Wireless pressure sensors measure the pressure of gases or liquids via a diaphragm and convert it into an electrical signal using a pressure-sensitive element.

A semiconductor piezoresistive diffusion pressure sensor forms a semiconductor strain gauge on the diaphragm’s surface. The diaphragm deforms under pressure, causing a change in electrical resistance due to the piezoresistive effect, which is then converted into an electrical signal. The piezoresistive effect is the change in electrical resistivity caused by applied stress, different from the piezoelectric effect, which is the polarization phenomenon caused by stress.

A capacitive pressure sensor forms a capacitor with a fixed glass electrode and a movable silicon electrode. The change in capacitance due to the deformation of the movable electrode under pressure is converted into an electrical signal.

Power Source

Wireless pressure sensors come in battery-powered and self-powered or energy-harvesting types. Battery-powered types use various batteries like button cells, AA, AAA, and lithium batteries.

Self-powered types do not require batteries and operate by collecting waste energy from surrounding heat, vibration, etc. Energy sources include temperature differences, vibrations, sunlight, and magnetic fields. This eliminates the need for battery maintenance and reduces operational costs.

Data Transmission

Wireless pressure sensors use various wireless communication methods for data transmission to data loggers, such as Wi-Fi, Zigbee, Lora, LoRaWAN, and Bluetooth. The suitable data communication method is chosen depending on the product and application. For instance, LoRaWAN offers excellent reception sensitivity and resistance to radio interference, allowing for communication distances of over 10 km in ideal environments, making it suitable for wide-area operations. Additionally, some products enable status checking via smartphones.

Types of Wireless Pressure Sensors

Overview

Wireless pressure sensors come in various types, each with different specifications and features. The pressure range, durability, and suitable applications vary by product, so it is necessary to select the appropriate one based on the intended use.

Data Management

Some products allow data to be saved in CSV format for statistical maintenance and management of equipment. Products with mechanical pressure gauges equipped with pressure sensors and communication modules enable pressure readings on-site even when communication is unavailable. Sampling intervals vary by product, from 0.1-second units to minute units, and some offer real-time data display.

Waterproof and Dustproof

Products with an IP65 waterproof rating can be used in wet environments or outdoors. While many products are unsuitable for corrosive gases and fluids, some can measure contaminated water, steam, and slightly corrosive fluids.

Products with explosion-proof certification can be installed in hazardous areas handling flammable gases, such as petrochemical plants, paint factories, and chemical plants.

What Is a Wireless Temperature Sensor?

A wireless temperature sensor is a device that measures temperatures, such as those in pipelines, without the need for wired connections like power cables.

Traditional wired temperature sensors often require long power cables and can have installation limitations. Wireless temperature sensors eliminate these restrictions, allowing for installation in desired locations. They are used in industrial applications for monitoring pipeline temperatures, internal concrete temperatures, and other temperature-related monitoring. Additionally, they are used in educational settings for science experiments. The power sources are mainly divided into battery-powered and self-powered types.

Uses of Wireless Temperature Sensors

The primary use of wireless temperature sensors is for temperature monitoring in industrial applications. Main uses include:

• Measuring pipeline temperatures
• Monitoring machinery conditions (e.g., pumps, motors, compressors, gearboxes in process industries and semiconductor plants)
• Measuring internal concrete temperatures
• Temperature monitoring in retail and food industries (e.g., supermarkets, greenhouses, cold storage rooms, aquaculture facilities, refrigerated trucks)

Specifically, pipeline temperature and machinery condition monitoring are applicable in a wide range of industries such as power plants, chemical plants, oil refineries, and food processing facilities.

Wireless temperature sensors are also utilized in educational settings. Temperature-related science topics are covered from elementary to high school levels, allowing for various uses. They are employed in various experiments, including supercooling, distillation, and heat of neutralization, and waterproof models can be used outdoors.

Principle of Wireless Temperature Sensors

Measurement Mechanism

Wireless temperature sensors detect temperatures using common temperature sensors like thermocouples, thermistors, and resistance temperature detectors (RTDs). A thermocouple is a temperature sensor that uses the electromotive force generated by connecting two different metals with a temperature difference. Thermistors and RTDs measure temperature by correlating material resistance with temperature.

Thermistors are characterized by their ability to measure narrow temperature ranges with high sensitivity and small size, while RTDs cover wide temperature ranges with good linearity but lower sensitivity than thermistors. There are two types of thermistors: NTC thermistors, which decrease in resistance linearly with temperature increase, and PTC thermistors, which increase in resistance non-linearly with temperature increase. Common materials used are semiconductor ceramics primarily composed of metal oxides such as nickel, cobalt, manganese, and iron. RTDs mainly use platinum, nickel, and copper.

Power Source

Wireless temperature sensors come in battery-powered and self-powered or energy-harvesting types. Battery-powered types use various batteries like CR2032 button cells, AA, AAA, and lithium batteries.

Self-powered types do not require batteries and operate by collecting waste energy from surrounding heat, vibration, etc. Energy sources include temperature differences, vibrations, sunlight, and magnetic fields. This eliminates the need for battery maintenance and reduces operational costs.

Data Transmission

Wireless temperature sensors use various wireless communication methods for data transmission to data loggers, such as Wi-Fi, Zigbee, Lora, LoRaWAN, and Bluetooth. The suitable data communication method is chosen depending on the product and application. For instance, LoRaWAN offers excellent reception sensitivity and resistance to radio interference, allowing for communication distances of over 10 km in ideal environments, making it suitable for wide-area operations.

Types of Wireless Temperature Sensors

Wireless temperature sensors come in various types, as mentioned earlier. They are categorized based on application, such as industrial pipeline measurement, machinery measurement, and scientific experiments in educational institutions.

The temperature measurement range varies by product, so selecting the appropriate one is necessary. Measurement intervals also vary by product, and some offer real-time data display. Products with IP66/IP67 waterproof ratings can be used in wet environments or outdoors.

Moreover, some products have explosion-proof certification, allowing installation in hazardous areas handling flammable gases, such as petrochemical plants, paint factories, and chemical plants.

What Is a Winch Rope?

A winch rope is a specialized rope used with a winch, a machine designed for lifting, lowering, pulling, and dragging heavy loads. Winch ropes, made from either synthetic fibers or metal, provide the necessary strength and flexibility to withstand harsh outdoor conditions and rigorous tasks.

Applications of Winch Ropes

Winches are employed in various applications including:

• Lifting loads
• Removing scaffolding components
• Elevating vehicles and machinery
• Pulling heavy objects during installation
• Extracting felled trees

Winches come in different types based on their power source: manual, electric, engine-driven, and hydraulic. Winch ropes are essential components used alongside these winches.

Winch ropes are not only used in industrial settings but also in numerous outdoor scenarios. They are utilized for vehicle recovery in off-road driving, mooring boats in marine environments, and pulling in emergency and rescue operations.

Principles of Winch Ropes

Winch ropes, made from synthetic fibers or metal, possess the following superior qualities:

• Strength
• Durability
• Weather resistance
• Abrasion resistance
• Heat resistance
• Corrosion resistance
• Rust resistance

Metal Winch Ropes

Metal winch ropes are typically made from steel or stainless steel. They are heavy, durable, and resistant to wear, performing exceptionally well in high-temperature environments. Stainless steel winch ropes, in particular, offer excellent corrosion, rust, heat, and abrasion resistance, with an attractive finish. They are known to last up to ten times longer in marine environments compared to traditional wire ropes.

Synthetic Fiber Winch Ropes

Synthetic fibers, such as common nylon and ultra-high molecular weight polyethylene (UHMW-PE), are used in manufacturing winch ropes. These ropes are lightweight, easy to handle, and flexible. They float on water, resist damage from UV rays, and do not store much kinetic energy, reducing the risk if they snap. They have minimal stretch and low water absorption.

Selecting Winch Ropes

When choosing the optimal winch rope, consider factors such as required load capacity, exposure to environmental conditions, and specific requirements for compatibility with the winch drum. Important characteristics to evaluate include breaking strength and resistance to UV rays and moisture.

For example, synthetic fiber ropes are suitable for wet and corrosive environments due to their resistance to water and chemicals. They also perform well outdoors due to their UV resistance. Conversely, steel and stainless steel cables are ideal for high-temperature environments or where sharp objects may pose a risk, thanks to their heat and abrasion resistance.

Types of Winch Ropes

Besides standard winch ropes, there are specialized types available. These ropes typically range from 5mm to 15mm in diameter.

Pre-Stretched Winch Ropes

Pre-stretched winch ropes undergo special processing to reduce stretch compared to regular ropes. They are ideal for applications where maintaining consistent rope length is crucial for precise lifting or pulling operations. Available in both steel and synthetic fibers, UHMW-PE versions offer around 10% improved breaking strength over conventional ropes.

Braided Winch Ropes

Braided winch ropes feature exceptional flexibility and tangle resistance. Typically made from synthetic fibers, these ropes offer superior strength and lightweight properties. Their braided construction enhances durability and resistance to abrasion and UV damage. These ropes float on water, do not twist, and provide high performance in a wide range of lifting and pulling tasks.

What Is an UHMWPE Rope?

UHMWPE (Ultra High Molecular Weight Polyethylene) rope is a high-strength, durable rope made from UHMWPE fibers.

These fibers consist of extremely long polyethylene chains aligned in the same direction, resulting in high molecular overlap and exceptional strength. UHMWPE ropes are commonly used in applications requiring high strength, such as marine operations, climbing, and outdoor recreational activities. They offer outstanding properties in terms of strength, durability, abrasion resistance, UV resistance, and lightweight characteristics.

Applications of UHMWPE Rope

Due to its superior strength and durability, UHMWPE rope is widely used in high-load and harsh environmental conditions. Key applications include:

• Maritime and offshore industries, including oil and gas, aquaculture, and wind power
• Mooring lines for various vessels, including fishing boats, yachts, and sailing vessels
• Use in aquaculture for fish farming
• Emergency towing lines and earthquake rescue operations
• Replacing wires in commercial trawling systems
• Deep-sea lifting projects
• Various underwater towing operations
• Crane operations on ships (experimental use)

The rope’s lightweight and buoyant properties make it easy to handle and ideal for precise maneuvering in emergency towing situations.

Principles of UHMWPE

Characteristics of UHMWPE

UHMWPE (Ultra High Molecular Weight Polyethylene) is a polyolefin resin with extremely long polyethylene chains, typically having a molecular weight ranging from 1 to 7 million, compared to 200,000 to 300,000 for standard polyethylene. Manufactured through wet or dry gel spinning processes, UHMWPE’s long molecular chains enhance intermolecular interactions, significantly increasing polymer backbone strength.
Key properties of UHMWPE include:

• High strength
• Abrasion resistance
• Impact resistance
• Chemical resistance
• UV resistance
• Hydrophobic nature
• Lightweight (density of 0.92 – 0.94, enabling buoyancy in water)

UHMWPE is classified as a thermoplastic resin and is considered one of the super engineering plastics. It is also known as HMPE (High Modulus Polyethylene) or HPPE (High Performance Polyethylene).

Properties of UHMWPE Rope

UHMWPE rope is one of the strongest ropes available on the market. It is lightweight, easy to handle, and floats on water due to its low density. Typically, it weighs about 1/8th as much as steel wire rope and is more compact, making storage more convenient.

The rope has a low friction coefficient and superior abrasion resistance, approximately 15 times greater than steel wire rope. It has minimal stretch, with a break elongation of around 3-4%, resulting in low recoil during breakage. The long polyethylene chains aligned in the same direction make the rope’s recoil predictable and safer compared to other materials with unpredictable recoil behavior.

Being hydrophobic, UHMWPE rope repels water and does not absorb moisture. Its chemically stable structure resists a variety of chemicals, except strong oxidizing acids, detergents, mineral acids, and oils. With a high melting point above 144°C, the rope maintains durability at high temperatures, while also retaining strength in low-temperature conditions. UV resistance further extends its usability in harsh environments.

Types of UHMWPE Rope

UHMWPE rope comes in various forms, including stranded and double-braided ropes. Stranded ropes are available in configurations like 3-strand, 8-strand, and 12-strand, with diameters ranging from 4mm to 80mm. Double-braided ropes feature a structure that prevents twisting, enhancing their durability and performance.

When selecting UHMWPE rope, it is crucial to consider breaking strength and specific usage conditions to choose the appropriate type for the intended application.

What Is Radio over IP?

Radio over IP (RoIP) represents a transformative technology, encompassing systems and products that empower remote radio communications, transcending conventional range limitations, through connectivity via IP networks like 4G, 5G, and satellite connections.

Enhancing Radio Reach with RoIP

Conventional Push-to-Talk (PTT) radios often encounter restrictions in communication range, a challenge addressed effectively by RoIP. By leveraging LAN infrastructure within buildings, RoIP bridges inter-floor communication gaps. Furthermore, in tandem with satellite networks, RoIP facilitates seamless communication across vast expanses.

Applications of Radio over IP

RoIP revolutionizes the communication landscape, extending the reach of traditional radio systems beyond their inherent range constraints. Integration with satellite communication networks forms a versatile network, facilitating connectivity across diverse locales.
Foremost among its applications is emergency communication during disasters, facilitating efficient coordination between remote command centers and disaster sites, or among multiple disaster zones. RoIP also enables connectivity between radios stationed at dispersed locations or mounted on vehicles.

In sectors such as events, security operations, and construction sites, where expansive coverage is paramount, RoIP emerges as an indispensable communication tool. Its versatility finds expression in:

• Multi-store retail stores and hotel communication networks.
• Surveillance applications, augmenting IP camera systems through on-site conversation monitoring.
• Dispatch services, streamlining coordination and task management.
• Inter-floor communication within buildings, enabling various functions such as calls, audio output to public address systems, or indicator light control.

Moreover, by harnessing LTE and other internet connections, RoIP extends communication coverage nationwide. Beyond two-way communication, radio broadcasts accessible via smartphones represent another dimension of RoIP functionality.

Principles of Radio over IP

Understanding PTT Radio Dynamics

Traditional radio communication revolves around direct signal transmission and reception within a shared frequency band. PTT radios, a prevalent variant, utilize a single frequency band. In PTT operations, transmission and reception alternate, precluding simultaneous transmission. A customary practice involves signaling the end of transmission with “over” to indicate completion.

Mechanism of Radio over IP

RoIP seamlessly transitions traditional PTT radio communications into IP-based interactions, enabling communication via IP-capable devices. Through RoIP gateways, it facilitates inter-group radio communication over the internet or satellite networks. Some products integrate with public address systems and indicator lights using audio and control terminals.

RoIP supports both long-distance communication via IP networks (bridge mode) and communication between radios and IP phones (converter mode).

Types of Radio over IP Products

RoIP products offer diverse functionalities, including gateway capabilities for VPN establishment and multiple input ports such as VoIP, POTS, and RoIP. Certain models feature mixing functions for seamless radio communication, while satellite-oriented products incorporate optimization technologies like packet aggregation and RTP header compression. Additional features may include USB recording and automatic channel switching, enhancing operational efficiency and versatility.

What Is an Encrypted Radio System?

An encrypted radio system stands as a pinnacle in wireless communication technology, employing encryption techniques to safeguard sensitive communication content against unauthorized access by third parties. In essence, it ensures confidentiality, a critical requirement in various applications where wireless communication is prevalent.

Encrypted radio systems operate by encrypting messages at the transmitting end and decrypting them upon reception, effectively thwarting eavesdropping attempts and preventing data breaches if intercepted. This level of security extends across a spectrum of frequencies, encompassing UHF, VHF, and broader wireless communication standards such as Wi-Fi, Bluetooth, and specialized business radio systems.

Applications of Encrypted Radio Systems

Originally stemming from military terminology, the term “COMSEC” (communications security) denotes the meticulous protection of communication confidentiality. Encrypted radio systems find predominant usage in sectors with stringent security demands, notably those intertwined with military and infrastructural operations.

Military operations rely extensively on encrypted radio systems for secure VHF and UHF communications, particularly aboard ships and helicopters. Beyond military applications, these systems are indispensable in various sectors, including:

• Public emergency services such as fire departments, police forces, and emergency medical services
• Transportation sectors ensuring secure communication in aviation, railways, and maritime operations
• Energy industries encompassing oil, gas, and power generation facilities
• Maintenance and security management across diverse infrastructural facilities
• Maritime and shipping operations ensuring secure communications amidst maritime logistics

These applications underscore the indispensable role of encrypted radio systems in critical infrastructure-dependent sectors.

Principles of Encrypted Radio Systems

Basics of Encryption
Encryption operates on the principle of transforming original data, termed plaintext, into ciphertext through an encryption process. Subsequently, decryption reverses this process, converting ciphertext back into plaintext. Encryption and decryption employ respective keys, akin to passwords, to secure data. Encryption methods include symmetric key encryption and public key encryption, with hybrid encryption techniques combining elements of both.

Symmetric Key Encryption

Symmetric key encryption, also known as secret-key or shared-key encryption, employs a single key for both encryption and decryption. While it offers faster processing speeds, securely sharing the encryption key between sender and receiver poses a challenge. Common algorithms include AES and RC4.

Public Key Encryption

Public key encryption, also known as asymmetric encryption, utilizes distinct keys for encryption and decryption. The receiver holds a public key, shared for encrypting data, and a private key, kept confidential for decryption. This eliminates the need to transmit the decryption key, enhancing security and simplifying key management. Notable methods include RSA, DSA, and ECDSA.

Types of Encrypted Radio Systems

Encrypted radio systems span a diverse array of applications, supporting conventional VHF and UHF radio communications alongside modern methods like Voice over IP (VoIP) and IP-based transmissions. Products range from encrypted RoIP (Radio over IP) transceivers to IP encryption devices facilitating secure interconnection of HF radios via IP networks and encrypted multiplexers. These systems accommodate traditional voice interfaces, fiber optic communications, and IP networks, seamlessly transitioning between plaintext and encrypted modes to meet evolving communication demands.

What Is Plastic Recycling Machine?

Plastic recycling machine refers to equipment used to manufacture recycled pellets from plastic waste.

When recycling plastic waste, the following processes are involved:

1. Cleaning of Contaminated Materials
2. Dehydration
3. Size Reduction with Shredders or Grinders
4. Drying and Volume Reduction
5. Manufacture of Recycled Pellets Using Extruders

Each of these processes is necessary to convert waste into pellets of appropriate size and shape, facilitating easy reuse or recycling. This promotes waste reduction and resource reuse.

Plastic recycling machines can refer to machines specific to these processes or those involved in multiple or all recycling stages.

Applications of Plastic Recycling Machines

Plastic recycling machine is used to manufacture recycled pellets from plastic waste for material recycling purposes. These pellets undergo mixing, melting, and molding processes to create various recycled products.

Materials commonly used for recycling include PET (Polyethylene Terephthalate), HDPE (High-Density Polyethylene), LDPE (Low-Density Polyethylene), and PP (Polypropylene).

Recycled plastics are used in various products such as:

• Bottles, containers, and packaging
• Furniture and household items
• Clothing, carpets, and textiles
• Footwear like sneakers
• Bags, films, and sheets
• Automotive parts
• Toys, stationery, and building materials

Principles of Plastic Recycling Machines

Plastic recycling machines can refer to machines specific to certain recycling stages or those involved in multiple stages. The main processes include:

1. Supplying Raw Material Waste via Feeders
2. Cleaning Contaminated Materials
3. Dehydration and Drying
4. Volume Reduction
5. Size Reduction with Shredders or Grinders
6. Pelletization: Manufacturing Recycled Pellets Using Extruders

Plastic waste materials like films, foams, non-woven fabrics, bags, and flakes are used as raw materials.

Types of Plastic Recycling Machines

Various machines are used in different recycling stages:

• Cleaning, Dehydration, and Drying Machines: Bottle washers, flake washers, screw press dehydrators, and dryers.
• Size Reduction Machines: Shredders, crushers, granulators, and grinders.
• Pelletization Machines: Extruders and pelletizers.

Integrated machines for multiple processes or complete recycling lines are also available, contributing significantly to efficiency in plastic recycling processes.