The steps are to connect the reference light source to the power meter using a clean and compatible connector, turn on the power meter and select the appropriate wavelength and unit settings, turn on the reference light source and wait for it to stabilize, read the displayed. The steps are to connect the reference light source to the power meter using a clean and compatible connector, turn on the power meter and select the appropriate wavelength and unit settings, turn on the reference light source and wait for it to stabilize, read the displayed. To use a power meter for fiber optic testing, always clean connectors first with lint-free wipes or click-to-clean tools. Select the correct wavelength and set your reference. You measure optical power in dBm or insertion loss in dB. Consistent procedures ensure accuracy. Typically both transmitters and receivers have receptacles for fiber optic connectors, so measuring the. To measure power, attach the meter to the cable that has the output you want to measure. tested and known to be fine) that is attached to the transmitter, acting as the 'source' to measure transmitter power. This Applications Engineering Note (AEN 135) explains and recommends standard measurement methods for characterizing optical fiber system performance. This note also provides background information on system link configurations, test equipment and system component considerations that influence. n optical fiber to a distant receiver.