IEC 61557-1-2019 pdf free.Electrical safety in low voltage distribution systems up to 1 000 Va.c.and 1500 Vd.c.-Equipment for testing,measuring or monitoring of protectivemeasures Part 1: General requirements.
uncertainty of measuring equipment
uncertainty of the result of a direct measurement of a measurand having negligible intrinsicuncertainty
Note 1 to entry: Unless explicitly stated otherwise,the measuring equipment uncertainty is expressed as aninterval with coverage factor 2.
Note 2 to entry: ln single-reading direct measurements of measurands having low intrinsic uncertainty withrespect to the measuring equipment uncertainty, the uncertainty of the measurement coincides, by definition, withthe measuring equipment uncertainty.Otherwise the measuring equipment uncertainty is to be treated as acomponent of category B in evaluating the uncertainty of the measurement on the basis of the model connectingthe several direct measurements involved.
Note 3 to entry: The measuring equipment uncertainty automatically includes, by definition, the effects due to thequantization of the reading values (minimum evaluable fraction of the scale interval in analogic outputs, unit of thelast stable digit in digital outputs).
Note 4 to entry: For material measures, the measuring equipment uncertainty is the uncertainty that should beassociated to the value of the quantity reproduced by the material measure in order to ensure the compatibility ofthe results of its measurements.
4 Requirements
4.1General requirements
Measuring equipment,when used for a designated purpose,shall not endanger persons,livestock or property.Furthermore,measuring equipment with additional functions not formingpart of the application of the lEC 61557 series shall also not endanger persons, livestock orproperty.
4.2Influence quantities – Operating uncertainty (B), percentage operating uncertainty.
The operating uncertainty shall be calculated by means of Equation 1:
4.3Rated operating conditions
The following rated operating conditions shall apply, except for insulation monitoring devices(IMD) in accordance with IEC 61557-8 and for insulation fault location systems (IFLS) inaccordance with lEC61557-9:
-temperature range from o C to 35°C;
– a position of ±90° from the reference position for portable measuring equipment;
85 % to 110 % of the nominal supply voltage for supply from the distribution systems (ifapplicable).The values in lEC 60038 shall be applied for a supply from the distributionsystem;
the charge condition in accordance with 4.4 shall apply to the battery or batteries/accumulators for measuring equipment with a supply from batterieslaccumulators;
the range of revolutions per minute stated by the manufacturer for measuring equipmentwith a supply from a hand-driven generator;
– frequency of the supply voltage +5 % (if applicable).
NOTE Additional rated operating conditions are stated in other parts of the lEC 61557 series.4.4Battery test facility
Measuring equipment with power supplied from dry or rechargeable battery cells shall testand indicate that the state of charge of these batteries will permit measurement within thespecification. This may be done automatically as part of the measurement cycle or as aseparate function. Where the battery test is a separate function, the test load shall be of thesame level as the one appearing during a measurement.
Measuring and monitoring equipment shall be in accordance with IEC 61010-1,IEC 61010-2-030,IEC 61010-031,IEC 61010-2-034 and, if applicable, IEC 61010-2-032,andwith the following additional requirements.IEC 61557-1 pdf download.