Intrinsically safe selection rules for isolated safety barriers

Intrinsically Safe Selection Rules for Isolated Safety Barriers

Introduction

Ensuring safety is crucial in industries where hazardous environments are present. One of the key components in maintaining safety is the use of isolated safety barriers. These devices play a vital role in preventing the propagation of electrical energy into explosive atmospheres. In this article, we will discuss the selection rules for intrinsically safe isolated safety barriers, which are designed and certified to minimize the risk of ignition.

1. Certification Standards

When selecting isolated safety barriers, it is essential to consider the certification standards they comply with. The most widely recognized certification standard for intrinsic safety is IEC 60079-11, which ensures that the equipment will not cause an explosion under normal or fault conditions. Additionally, other regional standards such as ATEX and UL also provide guidelines for selecting suitable barriers.

2. Hazardous Area Classification

Understanding the hazardous area classification is crucial when choosing isolated safety barriers. Different zones are classified based on the probability of the occurrence and persistence of explosive atmospheres. The barrier’s selection should align with the specific zone it will be installed in, taking into account factors such as gas types, temperature, and concentration levels.

3. Maximum Voltage and Current Ratings

Isolated safety barriers have maximum voltage and current ratings that need to be considered during the selection process. These values indicate the maximum electrical energy the barrier can handle without causing a spark or ignition. It is important to ensure that the selected barrier can safely accommodate the voltage and current levels present in the system.

4. Power Requirements

Different isolated safety barriers may have varying power requirements. Some barriers draw power from the connected control system, while others may require external power sources. It is important to assess the availability and feasibility of providing power to the barriers within the designated hazardous area.

5. Compatibility with Field Devices

Isolated safety barriers are often used in conjunction with field devices such as sensors, actuators, and transmitters. Compatibility between the barrier and field devices is crucial for proper operation and safety. Considerations should be made regarding the type of signals (analog or digital), communication protocols, and wiring configurations to ensure seamless integration.

6. Mounting and Installation

Proper mounting and installation of isolated safety barriers are essential for their effective operation. Consider factors such as space availability, environmental conditions, accessibility for maintenance, and ease of wiring during the selection process. Choose barriers that can be easily installed in the designated areas without compromising safety or functionality.

7. Maintenance and Diagnostics

Regular maintenance and diagnostics are crucial to ensure the ongoing reliability and effectiveness of isolated safety barriers. Select barriers that provide features such as fault indication, self-diagnostic capabilities, and easy-to-access terminals for troubleshooting. These features will facilitate timely identification and rectification of any issues that may arise.

Conclusion

Selecting the appropriate isolated safety barriers is essential for maintaining safety in hazardous environments. By considering certification standards, hazardous area classification, voltage and current ratings, power requirements, compatibility with field devices, mounting and installation requirements, and maintenance and diagnostic features, one can make informed decisions to ensure the barriers effectively mitigate the risk of ignition. Always consult with experts and follow industry guidelines when selecting and installing isolated safety barriers to ensure the highest level of safety in the workplace.