ONT LOPL CPE

Description

It occurs when the ONT transmissions continue to drift despite corrective action by the OLT. Transmitting outside the designated timeslot for that ONT can affect other ONTs transmissions. This is sometimes caused by ONTs that are on a loop that is too long or that the differential delay between the longest and shortest ONT is outside the 20-30km supported window. This may also occur if there are some hardware issues within the ONT.

Laser Safety

Warning! Personnel handling fiber optic cables must be trained for laser safety.

Warning! Optical Fibers emit invisible laser radiation. Avoid direct exposure to the beam. Never look into the end of a Fiber or into a Fiber connector on a cable or a device. Permanent eye damage or blindness can occur quickly from laser radiation.

Fiber Optic Cable

Ensure that the fiber connectors are properly cleaned per local standards. Dirty connectors may result in inaccurate measurements.

Caution: Fiber optic cable installation and maintenance should only be performed by trained service personnel.

Caution:  Do not bend the fiber optic cable to a diameter smaller than 7.5cm/3 inches. Doing so may damage the fiber or prevent the signal from passing through properly.

Trouble Clearing

The probable causes of this alarm are: 

• ONT Failure: It is possible that a malfunctioning ONT may cause this error. Locate and remove the ONT and verify that the alarm clears.
• Bad Fiber Splice: When a fiber has been improperly spliced and there is a rapid temperature change, the ONT LOPL CPE alarm may be seen. If this alarm is seen intermittently, then the fiber should be examined for improper splices.
• Fiber is Too Long: The Tellabs system only supports fibers of length 0-30km. If the fiber is longer than 30km, the round trip time on the fiber may be too high and interfere with other ONTs transmissions.