MT 1 - TC 23/MT 1

This International Standard applies to sound signalling devices with integral enclosures or to sound signalling devices intended to be fitted into or supplied with enclosures according to IEC 60670 intended for household and similar purposes with rated voltages greater than 50 V a.c. or 75 V d.c. and not exceeding 250 V a.c. or 250 V d.c., and with rated power inputs not exceeding 100 VA. This standard applies to fixed, portable and plug-in devices for indoor or outdoor use.