Methods for calibrating OLTS and determining optical loss

A method for calibrating an optical loss test set (“OLTS”), the method comprising:

• calibrating a first optical power meter of the OLTS using a stabilized light source, wherein the first optical power meter is in optical communication with a first test port of the OLTS, wherein a calibration cable is connected to the first test port and the stabilized light source during calibrating of the first optical power meter;
• calibrating a second optical power meter of the OLTS using the stabilized light source, wherein the second optical power meter and an internal light source of the OLTS are in optical communication with a second test port of the OLTS, and wherein the calibration cable is connected to the second test port and the stabilized light source during calibrating of the second optical power meter;
• and
• setting a power level of the internal light source using the calibrated first optical power meter, wherein the calibration cable is connected to the first test port and the second test port during setting of the power level, and wherein a connection of the calibration cable to the second test port is maintained between calibrating of the second optical power meter and setting of the power level.