The magnitude of this error is a function of both wavelength and connector type, and, as a result, the power meter should be calibrated with the same fiber and connector with which it is to be used. An optical power meter is the most common type of test equipment used to support fiber optic system. NIST developed a testing system to provide absolute power calibrations for optical power meters. Finding ways to optimize the performance of test equipment is one of the primary issues for managers, yet maintaining a large inventory of test and measurement equipment requires a systematic and efficient approach. Consistent procedures ensure accuracy.