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IEC 60947-8:2021 pdf download - Low-voltage switchgear and controlgear – Part 8: Control units for built-in thermal protection (PTC) for rotating electrical machines. 3 Terms and definitions, symbols and abbreviated terms 3.1 Terms and definitions For the...

IEC 60947-3:2015 pdf download - Low-voltage switchgear and controlgear – Part 3: Switches, disconnectors, switch-disconnectors and fuse-combination units. 4.3.1 .3 Rated impulse withstand voltage (U imp ) Subclause 4.3.1 .3 of IEC 60947-1 applies. 4.3.2 Currents An...

IEC 60938-2:2021 pdf download - Fixed inductors for electromagnetic interference suppression – Part 2: Sectional specification on power line chokes. 4 General requirements 4.1 General Units, graphical symbols, letter symbols and terminology shall be taken from the...

IEC 60938-1:2021 pdf download - Fixed inductors for electromagnetic interference suppression – Part 1: Generic specification. 4.3.3 Mounting The detail specification shall specify the method of mounting to be recommended for normal use and the method that...

IEC 60904-7:2019 pdf download - Photovoltaic devices - Part 7: Computation of the spectral mismatch correction for measurements of photovoltaic devices. All integrals shall be performed in the entire spectral range where the respective quantities are not...

IEC 60904-4:2019 pdf download - Photovoltaic devices – Part 4: Photovoltaic reference devices – Procedures for establishing calibration traceability. 3.6 traceability <of a PV reference device> requirement for any PV reference device, to tie its calibration value...

IEC 60904-3:2019 pdf download - Photovoltaic devices – Part 3: Measurement principles for terrestrial photovoltaic (PV) solar devices with reference spectral irradiance data. 1 Scope This part of IEC 60904 applies to the following photovoltaic devices for...

IEC 60885-3:2015 pdf download - Electrical test methods for electric cables – Part 3: Test methods for partial discharge measurements on lengths of extruded power cables 1 Scope This part of IEC 60885 specifies the test methods...

IEC 60876-1 :2014 pdf download - Fibre optic interconnecting devices and passive components – Fibre optic spatial switches – Part 1: Generic specification. 3.1.8 blocking inability to establish a connection from a free input port to a...