OWL VOLT-1 – Visual Optical Length Tester

OWL VOLT-1 – Visual Optical Length Tester

General Features

1. BRIGHT RED LASER TRANSMITTER – this ST connector port houses a laser diode that emits bright red visible light into an optical fiber.
2. CONTINUOUS WAVE/TEST SELECTOR SWITCH – this 3-way switch selects between OFF (center), length testing / fiber identification mode (right), and continuous wave mode (left).
3. DETECTOR PORT – this ST connector port houses a photodiode detector used to receive light from an optical fiber.
4. POWER LED – this LED indicates that the tester is powered on. During normal operation, if this LED is very dim or is not lit, this indicates that the battery may not have sufficient power for accurate testing, and should be replaced.
5. LED DISPLAY – this 7-segment LED is used to display the length of the fiber link in kilometers. If the display shows all dashes, the VOLT is not receiving enough light to make a measurement. This means that either the link is either too long to be measured or there is a problem with one of the fibers used for length measurement.

Applications

Fiber Length Measurement. The VOLT uses a “round robin” method of length measurement. This method requires two fibers from the same fiber cable to be looped back at one end with a patch cord. Light is injected into one of the fibers by the transmitter and is received by the detector connected to the other fiber. The round trip travel time is converted into length in kilometers and divided by two to arrive at the length of the fiber cable. It is not necessary to test each fiber for length; the length measurement applies to all fibers in the cable.

1. On one end of the fiber cable, loop back two of the fibers with one of the patch cords.
2. On the other end of the fiber cable, connect one patch cord to each of the fibers being used for the test. Connect the other end of the patch cords to the receiver and transmitter ports on the VOLT. It does not matter which patch cord connects to which fiber.
3. Power on the VOLT into length test mode by flipping the switch to TEST. In a few seconds, the display will show the length of the fiber in kilometers. In the example at right, the link is 1.250 kilometers.

NOTE: If the green indicator LED does not light up, the battery has insufficient power for a valid test, and must be replaced before continuing.

Visual Fiber Identification. The VOLT provides a flashing mode for easy visual fiber identification. Fibers are identified by locating the fiber end with the flashing red light on the opposite end of the fiber cable. This is useful for locating fibers that are marked incorrectly or not marked at all.

1. Connect the VOLT to the fiber you are testing via a patch cord as shown at right.
2. Power ON the VOLT into fiber identification mode by flipping the switch to TEST. This mode emits a flashing beam of high-intensity red light into the fiber.
3. Identify the fiber by looking for the flashing red light emitting from the connector.

Visual Fault Location. In Continuous Wave Mode, a steady beam of ultra-bright red laser light is injected into the fiber. If this light encounters a break or microbend in the fiber, the light will be redirected into the buffer. This light will be visible through the fiber jacket, informing the user of a break or microbend in the fiber.

1. Connect the VOLT to the fiber you are testing via a patch cord as shown at right.
2. Power ON the VOLT to visual fault location mode by flipping the switch to CW. If there is a fault in the first few meters of the fiber, red light should appear as a red glow through the fiber jacket.