1.1 This standard applies to the following electrical and electric measuring instruments:
——direct-acting indicating instruments;
——direct-acting recording instruments;
——indirectly acting instruments;
——certain accessories for these instruments. Note These instruments and their accessories are or will be covered by standards with special provis ons, hereinafter referred to as "relevant standards". These standards contain or will contain overviews of the instruments and accessories that determine the scope of the present standard. 1.2 This standard also applies to indicating and recording instruments containing electronic components as mentioned in section D. 1.3 This standard does not contain any special provis ons for instruments for use in special environments such as:
——weatherproof instruments;
——flameproof instruments;
——shock-resis ant instruments;
——vibration-proof instruments;
——intrinsically safe instruments;
——instruments for medical applications. Note Different or additional provis ons may apply to these instruments. 1.4 This standard covers only the safety provis ons and no other provis ons for indicating and recording instruments. It replaces the safety provis ons that may be included in the relevant standards. *) 1.5 In this standard:
——the term "instrument" continues to be used for indicating and recording instruments and their accessories referred to in 1.1;
——the terms voltage and current mean the effective value or the direct current value unless otherwis stated. 1.6 This standard specifies provis ons for indicating and recording instruments and their accessories to provide reasonable protection of persons and to prevent damage to the environment; the standard describes the test methods required to test the instruments against these provis ons and states the terminology used for safety problems. Note The safety of the instrument may also depend on the adaptation of its construction to the installation in which it is used.
NEN 3523-1984 history
1984NEN 3523-1984 Indicating and recording electrical measuring Instruments and accessories — Safety requirements