The introductory class in the professional measuring technique the model is suitable ideally for all professional applications up to 600 v by the large display with display of the allocation of monitoring socket by pressing the key the input impedance can be briefly reduced from 10 m to 400 k in order to avoid faulty measurements by stray voltages the various preventive measures are rounded off by resetting 400 a ma protection the annoying fuse changes are not applicable in 400 ma range