PCVFL (Precision Coupled Visual Fault Locator) is a light-weight, hand-held tool used to quickly troubleshoot faults in the continuity of both single mode and multi-mode fibers, especially at fiber launch points or in OTDR dead zones.

A high intensity visible red laser beam is precision-coupled into a optical fiber; breaks and micro-bends in the fiber deflect the red light into the fiber jacket, producing a red glow at the point of the fault.

The PCVFL can also be used as an end to end visual fiber identifier, which is useful for locating fibers terminated in poorly labeled on unlabeled fiber patch panels

The PCVFL unit is controlled with a single switch that toggles between OFF, CW(continuous wave), and pulse modes. The battery life of 15hrs in CW mode can be greatly extended by using pulse mode, which uses a 12.5% duty cycle, and can extend the battery life up to 120hrs of continuous use