What Does an Optic Fiber Ranger Do?

An Optic Fiber Ranger injects a laser pulse into the optical fiber and collects and checks the reflected light waves to assess the quality of an optic fibers’ reflective capabilities and detect malfunctions. It is more portable and cost-effective compared to a fiber optic OTDR.


Types of Optic Fiber Rangers

Visual Fault Detector (VFL)

The Optical Fiber Tester detects faults using the built-in visual fault detector. By testing the lengh of the fiber and the distance between the two nodes, the device determines the location of the failure point and the type of malfunction. The Optical Fiber Tester with VFL can accurately detect multiple faults.

Visual Fault Detector (VFL) for Fiber To The X (FTTx) network

The Optical Fiber Tester with built-in visual fault detector, suitable for Fiber To The X (FTTx) network installations and maintenance. It can be used to test any optical fiber to the loop network and detect faults such as breakpoints, poor connections, cracking above others. It adopts OTDR technical principles.

Loss Tester

The Optical Fiber Loss Tester is used to measure the return loss of the fiber optic linking. The data measured can be used to assess the quality of optic fiber end-face and optical fiber connectors. The device outputs various measurements, such as return and insertion loss above others.

Factors Affecting Selection of Optic Fiber Ranger

  1. The type of network – there are several broadband network architecture types, such as FTTx (Fiber To The X), Passive Optical Network, Active Optical Network above others. It is essential to find a suitable Optic Fiber Ranger to guarantee the best possible results.
  2. The lenght of the Optical Fiber Network – there are limitations to each of the Optic Fiber Rangers in terms of their measurement range. To ensure quality, the range should be chosen accordingly.
  3. Test Wavelength – the wavelength is essential for the accuracy of the measurement and error limitation. It is required to choose the according Optical Fiber Ranger with the test wavelength suitable for measuring the respective optical cables and networks. Otherwise, the faults can go undetected.
  4. Fault Detection Quantity – based on the network size, it is important to test for many faults efficiently and quickly. To test larger networks, it is important to choose an Optic Fiber Ranger that runs more simultaneous tests.
  5. Storage – each Optic Fiber Ranger has a limited storage space for the data measured. Larger storage space increases the efficiency at which the Ranger can be used.
  6. Cost – different features come at different costs and therefore, it is necessary to assess what capabilites of an Optic Fiber Ranger are required for a specific network. GAOTek offers a variety of Optic Fiber Rangers with various functions suitable for industry professionals.

What tests are done when using an Optic Fiber Ranger?

It is important to perform an ongoing maintenance of the optic fiber network to ensure the optimal performance and efficiency. The purpose of Optic Fiber Ranger testing is to locate, detect and measure the events of the network, providing technicians with a record of network’s characteristics, that could be used to schedule repairs or upgrades.

Fiber Continuity Test

By performing this type of test, it is possible to verify transmission through the network. It will detect gross fiber faults such as macrobends and fractures. It is also used to determine if the right optic fiber is connected to the right patch connector. To perform this test, Visual Fault Locator is used and by injecting the light pulse will display the entire network and automatically detect fiber breaks and other faults.

Optical Loss Measurement

This test is done by injecting known light pulse at one end of the network and measuring the output at the other end. It can indicate the different errors that occur within the network, such as defective connections.

Optical Power Measurement

The goal of this test is to measure the signal strength transmitted through the optical network once it is activated. It is mostly used to measure the performance of the optical network after the maintenance and can be useful to detect the effectiveness of the network throughout its lifetime.

Proactive Fiber Inspection

It is useful to do a Fiber End-Face inspection on the optic fiber network end-face and connections between optic fiber to ensure light passing through. A single fault in these places cause a significant insertion loss, back reflection and can even damage the equipment used to perform other tests.


To ensure a precise test, it is important to study the layout of optic fibers in within the network and have tools to measure the performance of several indicators. It is also essential to clean, pre-test and calibrate the Optic Fiber Rangers.