Standards World

IEC 60909-3:2003 pdf free download - Short-circuit currents in three-phasea.c. systems 1 Scope This part of lEC 60909 specifies procedures for calculation of the prospective short-circuitcurrents with an unbalanced short circuit in high-voltage three-phase AC systems operating...

IEC 60904-2:2015 pdf free download - Photovoltaic devices 4.3Additional requirements for reference modulesAdditional requirements apply to reference modules:a)Bypass diodes: - general reference modules,that are used to measure a range of module types andgeometries,should not contain bypass diodes....

IEC 60898-2:2003 pdf free download - Circuit-breakers for overcurrent protectionfor household and similar installations 1 Scope and object This clause of Part 1 is applicable except as follows:Addition at the end of the first paragraph: This standard...

IEC 60870-4:1990 pdf free download - Telecontrol equipmentand systems lt is intcnded that this part serves as a common platform for thesystem planner and the 'supplier or manufacturer ofteiecontroisystems. The system planner will find the contentshelpful indetermining...

IEC 60825-12:2004 pdf free download - Safety of laser products 1Scope This part of lEC 60825 provides requirements and specific guidance for the manufacture andsafe use of laser products and systems used for point-to-point or point-to-multipoint freespace...

IEC 60812:2018 pdf free download - Failure modes and effects analysis (FMEA and FMECA) For large or complex systems (e.g. a railway), it might be necessary to sub-divide the systeminto subsystems (e.g. rolling stock,signalling，control room) for each...

IEC 60751:2008 pdf free download - Industrial platinum resistance thermometers and platinum temperature sensors 3.2 insulation resistance electrical resistance measured between any part of the electric circuit and the sheath atambient or elevated temperatures and with a...

IEC 60704-2-13:2011 pdf free download - Household and similar electrical appliances -Test code for the determination ofairborne acoustical noise Air-extraction range hoods shall be loaded using a pipe connected to a muffler according toFigure 101.The pipe shall...

IEC 60439-2:2005 pdf free download - Low-voltage switchgear andcontrolgear assemblies 2.3.11 flexible busbar trunking unit busbar trunking unit having conductors and enclosures designed to be bent during installation 2.3.12 busbar trunking feeder unit busbar trunking unit serving...