How accurate is an OTDR?

Assuming typical fiber attenuation of 0.20 dB/km at 1550 nm and splices every 2 km (loss of 0.1 dB per splice), a unit such as this one will be able to accurately certify distances of up to 120 km.

What is acceptable dB loss for fiber?

For singlemode fiber, performance should be at least 0.5 dB/km at 1310 and 1550 nm for outside-plant applications, and 1.0 dB/km for inside-plant applications at both 1310 and 1550 nm . 2) Determine connector loss.

What test capability can be done by OTDR?

The Optical Time Domain Reflectometer (OTDR) is useful for testing the integrity of fiber optic cables. It can verify splice loss, measure length and find faults. The OTDR is also commonly used to create a “picture” of fiber optic cable when it is newly installed.

What are the main measurement parameters used in OTDR?

OTDR Parameters

• Pulse Width. Setting the adjustable pulse width determines the duration of the pulse being emitted into the fiber link.
• Dead Zones.
• Distance Range.
• Averaging Time.

How do you analyze OTDR results?

However, if the spliced fibers are mismatched, the splice may appear on the OTDR trace as a gain. Here’s an example. If a splice goes from a larger core fiber to a smaller one, the difference in backscatter coefficients will show on the OTDR as a gain in light.

What is the dead zone in OTDR?

The OTDR dead zone refers to the distance (or time) where the OTDR cannot detect or precisely localize any event or artifact on the fiber link. It is always prominent at the very beginning of a trace or at any other high OTDR reflectance event.

What is a good fiber dB reading?

The optical power meter usually reads in dBm for power measurements or dB with respect to a user-set reference value for loss. For multimode fiber, an OLTS using a LED source will usually measure over a range of 0-30 dB, more than adequate for most multimode cable plants which are under 10 dB loss.

How do you read an OTDR report?

How to Read Your Trace. OTDR displays will show a Y and X axis. The X axis measures distance, and the Y axis measures attenuation and reflection in dB. Before running your trace, select the appropriate fiber network length, pulse width and acquisition time.

How do you test for OTDR?

Test Procedure

1. Turn on OTDR and allow time to warm-up.
2. Clean all connectors and mating adapters.
3. Attach launch cable to OTDR. Attach receive cable (if used) to far end of cable.
4. Set up test parameters on OTDR.
5. Attach cable to test to end of launch cable. Attach receive cable (if used) to far end of cable.
6. Acquire trace.

How long does an OTDR test take?

It typically takes at least 3 minutes for a skilled OTDR technician with high-quality equipment to obtain one trace. Printing out the trace adds another 2 to 3 minutes per fiber. In a system of only 48 fibers, this adds approximately 5 man-hours, including set-up time, to the testing procedure.

Which wavelength is recommended for OTDR testing?

Generally speaking, 1625 nm is the preferred wavelength for monitoring legacy 1310/1550-nm systems, largely due to laser cost. The 1650-nm wavelength is recommended for CWDM, DWDM, XGS-PON, and TWDM-PON systems where the traffic wavelengths extend into the L-Band.

What is the difference between a TDR and an OTDR?

Essentially an optical time domain reflectometer, OTDR is the equivalent of an electronic TDR, but for optical fibres. It then receives and analyses the light that is scattered by Rayleigh backscatter or reflected back from points along the fibre.

What is the purpose of OTDR test?

Answer Wiki. The Optical Time Domain Reflectometer (OTDR) is important for testing the integrity of fiber optic cables. It can verify splice loss, measure the length and find faults. The OTDR is also commonly used to create a “picture” of fiber optic cable when it is newly installed.

What is optoptical time domain reflectometer (OTDR)?

Optical Time Domain Reflectometer (OTDR) which is a measurement device that works indirectly on the fibre optic cables. It measures losses of data and finds faults in the optic cable.

What is the Aveis OTDR?

The Aveis OTDR is specifically designed for tough outdoor jobs because it is lightweight and easy operation, with the waterproof performance at the IP65 level. It can work continuously for more than 12 hours, making itself perfect for field testing.

What is an OTDR test for fiber optic lines?

“OTDR” stands for Optical Time-Domain Reflectometer. This is generally considered a piece of test equipment that does for fiber optic lines what a Line Reflectometer does for telephone lines and transmission cables. In some sense, a reflectometer functions like a radar channeled through a transmission line.