This Recommendation:

– gives the characteristics of metal oxide varistors (MOVs) used in accordance with [b-ITU-T K.11] for the protection of power supply circuits and signal circuits of telecommunication installations against overvoltages;

– does not deal with combinations of MOV with other over voltage protective component such as gas discharge tube (GDT), avalanche breakdown diode (ABD), etc.;

– does not deal with mountings and their effect on MOV characteristics, the characteristics apply to MOV as a component, mounted only in the ways described for the tests;

– does not deal with mechanical dimensions;

– does not deal with quality assurance requirements.