The basic process is straightforward: turn the meter on, set it to the correct wavelength, clean your connectors, plug in, and read the display. But getting accurate, meaningful results depends on understanding a few key details about wavelength settings, reference levels, and. This is your "QuickStart" guide to testing optical power in fiber optic communications systems with a fiber optic power meter. We'll give you the basic information you need and provide some printable references. Consistent procedures ensure accuracy. Using a visible light source tests the continuity of fiber optic cabling. Because fiber optic transmissions work in the infrared portion. Optical power meters (OPMs) and laser sources (LS) are essential tools for measuring signal strength and loss.