European Committee for Electrotechnical Standardization

Methods of Measurement of Touch Current and Protective Conductor Current
 N EN 60990

Annotation

This International Standard defines measurement methods for

– d.c. or a.c. current of sinusoidal or non-sinusoidal waveform, which could flow through the human body, and

– current flowing through a protective conductor.

The measuring methods recommended for TOUCH CURRENT are based upon the possible effects of current flowing through a human body. In this standard, measurements of current through networks representing the impedance of the human body are referred to as measurements of TOUCH CURRENT. These networks are not necessarily valid for the bodies of animals.

The specification or implication of specific limit values is not within the scope of this standard. IEC TS 60479 series provides information regarding the effects of current passing through the human body from which limit values may be derived.

This standard is applicable to all classes of EQUIPMENT, according to IEC 61140.

The methods of measurement in this standard are not intended to be used for

– TOUCH CURRENTS having less than 1 s duration,

– patient currents as defined in IEC 60601-1,

– a.c. at frequencies below 15 Hz, and

– currents above those chosen for ELECTRIC BURN limits.

This basic safety publication is primarily intended for use by technical committees in the preparation of standards in accordance with the principles laid down in IEC Guide 104 and ISO/IEC Guide 51. It is not intended for use by manufacturers or certification bodies independent of product standards.