Description: nominal plane specified by a measurement standard to ensure comparability of results; Name: reference level
Description: horizontal plane for use as the datum for height measurement; Name: Reference plane
Description: voltage which, together with the rated operating current, determines the use of the device and to which the various tests and the use categories refer. With single pole devices the rated rated operating voltage is generally the voltage over the pole. With multi-pole devices it is generally given as chained voltage; Name: Operating voltage