OLTS: Optical Line Termination Systems Guide

OLTS Optical Line Termination Systems featured image

Optical loss test sets (OLTS) are essential tools in the field of fiber optic communication. They are utilized for measuring the total amount of loss a fiber optic cable experiences, ensuring that the link can meet loss requirements for various applications. These dual-ended instruments assess length, optical return loss, and validate continuity, providing accurate and reliable information for technicians assessing fiber optic cabling systems.

As an integral component in the testing and maintenance of fiber optic networks, OLTS play a crucial role in the overall performance and efficiency of communication systems. They aid technicians in diagnosing and addressing potential issues, allowing for the optimization and integrity of the network. By understanding the capabilities and functionalities of OLTS, professionals in the industry can ensure networks are built and maintained with the highest possible quality and reliability.

Key Takeaways

  • OLTS are vital for measuring total loss in fiber optic cables and validating link requirements
  • They provide accurate assessments of length, optical return loss, and continuity
  • OLTS are essential to ensuring optimal performance and efficiency in fiber optic networks

Understanding OLTS

Performance of OLTS

An Optical Loss Test Set (OLTS) is a device used for testing the performance and integrity of a fiber optic cable. The primary function of an OLTS is to measure the amount of optical loss or attenuation in a fiber optic link. It works by injecting a known light source into the fiber and measuring the power level at the opposite end.

When testing a fiber optic network with an OLTS, technicians can evaluate the overall performance, including the loss at joints, connectors, and splices, as well as evaluate the quality of the fiber itself. The results obtained from an OLTS test can help determine the efficiency of the network and identify potential issues that may need attention.

Applications of OLTS

OLTS is used in various applications across different industries that require fiber optic networks. Some of these applications include:

  • Telecommunications: In this industry, OLTS is used to test and maintain the optical fiber infrastructure that supports voice, data, and video transmission.
  • Data Centers: OLTS is a crucial tool for ensuring the proper functioning of fiber links in data centers, where high-speed data transfer and connectivity are critical.
  • Enterprise Networks: Large businesses and organizations with extensive optical fiber infrastructure use OLTS to monitor the performance of their networks and ensure uninterrupted service delivery.
  • Industrial and Research Applications: OLTS can be employed in research facilities and industrial settings that utilize fiber optics in various processes and experiments.

Differences Between OLTS and Other Devices

While OLTS is an essential tool for measuring fiber optic link performance, there are other devices used in the testing and maintenance of such networks. One of these devices is the Optical Time Domain Reflectometer (OTDR). Although both OLTS and OTDR are used for fiber optic testing, they serve different purposes and offer unique benefits.

OLTS primarily focuses on measuring the total loss in a fiber link, while an OTDR can provide a more detailed view of the network. It works by sending a series of pulses into the fiber and analyzing the back-reflected and scattered light. This allows the OTDR to identify the exact location of faults, breaks, and losses within the fiber.

In summary, OLTS is a crucial tool for evaluating the performance of a fiber optic network, while an OTDR provides a detailed look at the integrity of the fiber itself. Both devices play vital roles in the testing and maintenance of fiber optic links and are necessary for ensuring the efficient functioning of these networks.

Installation and Maintenance of OLTS

Installation Process

Installing an Optical Loss Test Set (OLTS) involves following some essential steps to ensure proper functioning. First, unpack and inspect the device for any signs of physical damage. Next, familiarize yourself with the components and user manual for specific instructions on setup and operation.

Before connecting the OLTS to the fiber optic link, it’s crucial to clean the connectors to prevent contamination. Use a fiber cleaning tool or isopropyl alcohol to remove any dirt or debris from the connectors. Once the connectors are clean, connect the device to the link and perform an initial calibration according to the manufacturer’s guidelines. This step helps ensure accurate measurements.

Maintenance Procedures

Regular maintenance of OLTS is crucial for accurate and reliable testing results. Maintenance procedures include:

  • Calibration: Perform calibration checks following the manufacturer’s recommendations. Proper calibration ensures accurate test results and prevents false readings.
  • Cleaning: Regularly clean the connectors and adapters using a fiber cleaning tool or isopropyl alcohol to prevent contamination.
  • Storage: Properly store the device when not in use in a dry, cool environment to protect it from damage and extend its lifespan.

Troubleshooting Common Issues

Troubleshooting OLTS issues typically begins with identifying the problem at hand. Some common issues and their solutions include:

  • Inaccurate test results: If the OLTS provides results that seem inaccurate, recalibrate the device according to the manufacturer’s guidelines, and ensure connectors are clean.
  • Display issues: If the display is not functioning correctly or showing unreadable data, try resetting the device or updating the firmware.
  • Connection problems: If the OLTS cannot establish a connection with the fiber optic link, inspect the connectors and cables for damage and ensure they’re clean and free of debris.
  • Breaks in the fiber optic link: An Optical Time Domain Reflectometer (OTDR) can be used alongside an OLTS to help identify and locate breaks within the fiber optic link. This approach allows for a thorough understanding of any issues within the fiber infrastructure.

By following these procedures in the installation, maintenance, and troubleshooting of OLTS devices, technicians can ensure high-quality fiber optic network performance and minimize downtime.

Testing With OLTS

Use of OTDR in Testing

Optical Time Domain Reflectometer (OTDR) and Optical Loss Test Set (OLTS) are both valuable tools for testing fiber optic cables. While OLTS is mainly used to measure loss in power and attenuation, OTDR serves to identify issues such as breaks, bends, and other anomalies in a fiber link. Combining the usage of both OLTS and OTDR provides a complete testing and certification strategy for fiber optic installations.

Power Meter Usage

An essential component of an OLTS is the power meter, which measures the optical power present in the fiber. The power meter connects to the opposite end of the fiber link from the light source, detecting and quantifying the light emerging from the fiber optic. By comparing the input and output power, technicians can assess signal loss and determine the quality of the fiber link.

Fiber Link Testing

When testing a fiber link with an OLTS, the first step is establishing continuity and determining the link’s length. By sending a test signal through the fiber, the OLTS can measure the time it takes for the light to travel along the link and calculate the length accurately. This process helps confirm that the fiber link is intact and provides essential information for comparing expected versus measured losses.

Continuity and Attenuation Measurements

During the testing process, OLTS measurements focus on the continuity and attenuation of the fiber link. Continuity testing verifies that the link is able to transmit light from end-to-end without any breaks or obstacles in the signal path. Attenuation, on the other hand, is the reduction in power of an optical signal as it passes through the fiber. OLTS measures attenuation by calculating the difference between the input and output power levels, providing essential information for evaluating overall fiber link performance.

Fresnel Reflections

Another aspect that OLTS may measure is Fresnel reflections, which are caused by the light reflecting back from the interfaces between different refractive indices in the optical system. These reflections can disrupt the transmission of optical signals and cause signal loss. Measurement of Fresnel reflections can help technicians identify potential problem areas in the fiber link and take corrective actions accordingly.

Using OLTS in conjunction with OTDR and power meter readings enables comprehensive fiber optic cable testing, ensuring optimal performance and adherence to industry standards.

Benefits and Challenges

Advantages of OLTS

OLTS (Optical Loss Test Set) is a valuable tool in the field of fiber optic testing. One of the primary benefits of using an OLTS is its ability to accurately measure the total loss on a fiber link. This enables technicians to ensure the link meets the loss requirements for specific applications as per industry standards.

Another advantage of OLTS is its ability to measure length and optical return loss. By testing the fiber link’s continuity, an OLTS can help technicians identify potential issues that may affect the overall performance of the network.

OLTS devices are often dual-ended, meaning they require two technicians to perform the test. Despite the need for additional personnel, this feature allows for more accurate and efficient testing as the measurement is taken from both ends of the fiber link.

Potential Challenges

While OLTS offers numerous benefits, there are some potential challenges associated with its use. One challenge is the additional manpower required to perform the test, as OLTS devices are dual-ended. This can be a potential issue for organizations with limited personnel or resources.

Another potential challenge is the inability to detect and locate specific events or faults within the fiber cable. OLTS is primarily designed to test the overall loss on a fiber link but cannot provide detailed information on local faults or events. In such cases, a complementary tool like an OTDR (Optical Time Domain Reflectometer) may be required to pinpoint the location of any faults or events affecting the link.

In conclusion, OLTS offers many advantages for fiber optic testing, such as accurately measuring total loss and ensuring the link meets industry standards. However, it does come with some potential challenges, like the need for additional manpower and the inability to locate specific faults within the fiber cable. By acknowledging and addressing these challenges, technicians can maximize the benefits of using an OLTS.

Comparison of OLTS and PON

Combo PON and OLTS

Combo PON and OLTS make it possible for network operators to offer a comprehensive solution for broadband services. In a typical PON setup, an Optical Line Terminal (OLT) is used by the network operator to convert Ethernet signals to frames and transfer them through the network. The OLT is the starting point for a PON, connected to an aggregation switch via Ethernet cables. In a system that combines PON and OLTS technologies, the OLT can support both GPON (Gigabit Passive Optical Network) and XGS-PON (10 Gigabit Symmetric Passive Optical Network) on a single platform.

  • Offers flexibility in network deployment
  • Allows for smooth migration between PON technologies
  • Provides scalable capacity and future-proof connectivity

Installation of GPON with OLTS

GPON (Gigabit Passive Optical Network) is a popular PON technology that utilizes an OLT in conjunction with optical splitters and Optical Network Units (ONUs) to distribute data over fiber-optic networks. The installation of GPON with OLTS typically involves:

  1. Deploying the OLT at the service provider’s central office
  2. Connecting the OLT to an aggregation switch via Ethernet cables
  3. Installing optical splitters along the network to distribute signals
  4. Connecting ONUs at the customer premises to receive and transmit data

By using an OLTS as part of a GPON network, service providers can ensure reliable and scalable broadband access for their customers.


XGS-PON is an advanced PON technology that supports transmission speeds of up to 10 Gbps, making it suitable for high-capacity broadband services. To leverage XGS-PON, an OLTS must have:

  • Support for 10 Gbps symmetric downstream and upstream speeds
  • Compatibility with XGS-PON standards and equipment

An OLTS designed for XGS-PON can efficiently handle the increased traffic requirements and enable service providers to offer ultra-high-speed broadband services to their customers. By combining OLTS capabilities with XGS-PON technology, network operators can empower their clients with enhanced performance and future-proof networking solutions.

Use Cases and Training

Case Study: Anthony Richardson

Anthony Richardson, an experienced fiber optic technician, was assigned to a team responsible for installing and testing fiber optic networks. As part of his role, he started using an Optical Loss Test Set (OLTS) to measure the length and optical loss, as well as check the polarity of the installed links. The OLTS allowed Anthony and his team to perform these tests accurately and reliably, ensuring that their network installations met the necessary loss requirements for various applications.

OLTS Training Week 1

During the first week of training, the team focused on understanding and practicing the fundamental aspects of using an OLTS. The training curriculum covered the following topics:

  • Introduction to OLTS:. The team learned what an OLTS is, its components, and how it can benefit their work.
  • Measurement Techniques:. Hands-on practice sessions, during which the team learned how to take accurate readings and record loss values.
  • ISO Compliance:. Familiarization with ISO standards related to fiber optic testing, such as loss budgets and acceptable limits, helped ensure the team’s work aligned with industry best practices.

Software Utilization

Part of the OLTS training involves learning how to utilize the accompanying software effectively. This software can help the team analyze test results, generate reports, and manage the data collected during the testing process. As the team improves their software usage proficiency, they will be better equipped to troubleshoot, maintain, and optimize the fiber optic networks they work on. By combining proper OLTS training and software utilization, technicians like Anthony Richardson can enhance their skill sets and contribute to a more efficient and reliable fiber optic infrastructure.

Additional Uses of OLTS

Sports Broadcasting: NFL

The Optical Loss Test Set (OLTS) has proven to be a valuable tool in various industries, including sports broadcasting. In the NFL, for example, reliable and high-quality fiber optic connections are essential for transmitting live game footage to viewers around the world. The OLTS can be used to test and certify the performance of these fiber cables, ensuring that data transmission is seamless and uninterrupted. This is particularly important for high-profile games, like matches between popular teams like the Jaguars and Bears, where millions of viewers are tuned in and expecting a flawless broadcast.

Security Integrations

Another area where OLTS plays a critical role is in security integrations. As modern security systems increasingly rely on fiber optic networks for communication and data transfer, the performance and reliability of these networks become crucial. In this context, OLTS can be used for testing and certifying the fiber cables that connect various components of a security system.

For example, OLTS can help measure the distance between security cameras and monitoring stations, ensuring that there are no signal losses over longer distances. Additionally, OLTS can be employed to troubleshoot potential issues in a network and help identify any weak points. By using OLTS, security professionals can have confidence in the performance and stability of their networks, ensuring the ongoing safety and security of their assets.

Frequently Asked Questions

What is the purpose of an OLTS in fiber testing?

An Optical Loss Test Set (OLTS) is a dual-ended tool used in fiber optic telecommunications to quickly test the total amount of loss in a fiber link. It measures length, optical return loss, and validates the continuity of the fiber. OLTS devices typically perform single-fiber testing on both single-mode (SM) and multimode (MM) wavelengths, providing accurate and efficient results.

How does OLTS testing differ from OTDR testing?

OLTS testing mainly focuses on determining the total loss of a fiber optic link, while an Optical Time-Domain Reflectometer (OTDR) is used to measure the overall length of the fiber and identify the location of any events or faults. OLTS testing requires two technicians and testing at both ends of the fiber. In contrast, OTDR testing usually involves a single technician working on only one end of the fiber.

What are the standard procedures for using an OLTS?

Using an OLTS typically involves the following steps:

  1. Calibration of the OLTS device, ensuring accurate measurements.
  2. Preparation of the fiber under test, including cleaning the connectors and splices.
  3. Connection of the OLTS to the fiber at both ends.
  4. Selection of the appropriate wavelength and measurement modes.
  5. Execution of the test, ensuring both technicians are in sync.
  6. Analysis and documentation of the test results.

Which brands offer reliable OLTS devices?

Several reputable brands offer OLTS devices, including EXFO, AFL, VIAVI, and Fluke Networks. These companies provide a range of different OLTS devices and configurations suitable for various fiber testing requirements.

Can OLTS be used as a substitute for a power meter?

While an OLTS can measure the power loss in a fiber link, it cannot replace a power meter. Power meters measure the absolute power of transmitted light in a fiber optic system, while an OLTS focuses on the relative loss between the two ends of the fiber. Power meters provide a more precise measurement of power levels and are essential for monitoring system performance.

How can OLTS results be converted to PDF format?

OLTS results can be converted to PDF format using the accompanying software provided by the OLTS manufacturer or with third-party software that supports the specific device. By exporting the results to PDF, the data can be easily shared, stored, and analyzed independently from the OLTS device.

Last Updated on September 22, 2023 by Josh Mahan

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