Zener & Galvanic Barriers

Zener and galvanic barriers are two types of electrical protection devices used in hazardous or explosive environments to prevent the ignition of flammable gases, vapours, or dust. These barriers act as a shield, preventing the ignition of these substances by limiting electrical energy and providing isolation between hazardous and non-hazardous areas. They are commonly employed to help guarantee industrial workplace safety and industrial electrical safety in settings such as oil refineries, chemical plants, and mining operations.

What are Zener Barriers?

A Zener barrier is an intrinsically safe device used to limit electrical energy and prevent the transfer of excess voltage or current from the non-hazardous area to the hazardous area. It employs a Zener diode, which is a special type of diode that conducts electricity in reverse bias when the voltage across it exceeds a specific value known as the Zener voltage. By utilising the Zener effect, these safety barriers regulate the energy entering the hazardous area below the level that could cause ignition. Zener safety barriers are commonly used to protect intrinsically safe circuits and devices, such as sensors, transmitters, and switches.

What are Galvanic Barriers?

A galvanic barrier, also known as an electrical isolator, isolation barrier, or galvanic separator, is another type of protection device used in hazardous environments. It provides electrical isolation between the hazardous area and the non-hazardous area, preventing the flow of direct current (DC) or low-frequency alternating current (AC) while allowing the transmission of signals or data. Galvanic barriers utilise transformers or optocouplers to provide the necessary isolation. These barriers are commonly employed to protect instruments, control systems, and communication interfaces from potentially hazardous electrical faults, surges, or short circuits.

What is a SIL 2 Galvanic Barrier?

A SIL 2 galvanic barrier is a specific type of galvanic isolator that meets the Safety Integrity Level (SIL) 2 standard. The SIL is a measurement of a safety function's reliability and performance.

A SIL 2 galvanic barrier provides a higher level of safety and reliability compared to standard galvanic isolators, making them suitable for critical applications where safety is paramount.

Zener and Galvanic Barrier Applications

Zener and galvanic barriers are commonly used in various applications where electrical circuits and equipment need to be protected in hazardous environments. Some of the applications where these barriers are utilised include:

• Process Control Systems: Zener and galvanic barriers are widely used in process control systems found in industries such as oil and gas, chemical manufacturing, and pharmaceuticals. They provide protection for sensors, transmitters, and other control devices located in hazardous areas, ensuring safe and reliable operation.
• Industrial Automation: In industrial automation applications, Zener and galvanic barriers are employed to protect programmable logic controllers (PLCs), distributed control systems (DCS), and other automation equipment. These barriers safeguard the communication interfaces and control signals between the hazardous and non-hazardous areas.
• Instrumentation and Measurement: Zener and galvanic barriers are crucial for protecting measurement and instrumentation equipment used in hazardous environments. This includes devices such as pressure transmitters, temperature sensors, level indicators, data loggers, and flow meters. The barriers ensure accurate data acquisition and control without posing a risk of ignition.
• Power Distribution: Zener and galvanic barriers play a role in hazardous area power distribution systems. They are used to isolate and protect electrical circuits that supply power to equipment located in potentially explosive atmospheres, preventing the transfer of excessive voltage or current.
• Communication and Networking: In hazardous environments, Zener and galvanic barriers are used to safeguard communication and networking equipment, such as fieldbus systems, Ethernet switches, RF transmitters, and wireless devices. They protect against electrical faults and potential ignition sources that could occur during data transmission.

How to Choose the Right Zener and Galvanic Barriers for Your Needs

Selecting appropriate Zener or galvanic barriers involves assessing:

• Hazardous Area Classification: Determine the specific zone and gas group of the hazardous area.
• Signal Type: Consider the type of signal being transmitted (e.g., analog, digital).
• Voltage and Current Ratings: Choose barriers with ratings that match your equipment's requirements.
• Safety Integrity Level (SIL): Opt for SIL 2 rated barriers for critical applications.
• Certifications: Ensure the barriers comply with relevant safety standards (e.g., ATEX, IECEx).

RS is a reliable provider of high-quality Zener barriers and galvanic isolators in Hong Kong. Carrying renowned brands like Turck, Phoenix Contact, Pepperl + Fuchs, and GEORGIN, RS provides ample options to find the best Zener barrier or galvanic isolator for any industrial or commercial application.

How to Order Zener and Galvanic Barriers from RS HK?

RS Hong Kong’s simple, straightforward ordering process makes it a breeze to obtain the Zener safety barriers and galvanic separators you need. Browse our online catalogue, select the desired products, and add them to your cart.

How Delivery Works at RS Hong Kong

RS Hong Kong is committed to providing efficient delivery services for our Zener and galvanic barriers. We offer a range of delivery options to suit different business needs. For more details, please visit ourDelivery Information page.