7/27/2019 Module 7 Assignment Info
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Conductor sizing and protectiono Conductor sizing: methodology
and definitiono Overcurrent protection principleso Practical values
for a protective schemeo Location of protective deviceso Conductors
in parallel
Practical method for determining the smallest allowable
cross-sectional area of circuitconductors
o General method for cable sizingo Recommended simplified
approach for cable sizingo Busbar trunking systems
Determination of voltage dropo Maximum voltage drop limito
Calculation of voltage drop in steady load conditions
Short-circuit currento Short-circuit current at the secondary
terminals of a MV/LV distribution
transformer
o 3-phase short-circuit current (Isc) at any point within a LV
installationo Isc at the receiving end of a feeder as a function of
the Isc at its sending end
Particular cases of short-circuit currento Calculation of
minimum levels of short-circuit currento Verification of the
withstand capabilities of cables under short-circuit conditions
Protective earthing conductoro Connection and choice for
protective earthing conductoro Sizing of protective earthing
conductoro Protective conductor between MV/LV transformer and the
main general
distribution board (MGDB)
o Equipotential conductor The neutral conductor
o Sizing the neutral conductoro Protection of the neutral
conductoro Breaking of the neutral conductoro Isolation of the
neutral conductor
http://www.electrical-installation.org/enwiki/Conductor_sizing_and_protectionhttp://www.electrical-installation.org/enwiki/Overcurrent_protection_principleshttp://www.electrical-installation.org/enwiki/Overcurrent_protection_principleshttp://www.electrical-installation.org/enwiki/Practical_values_for_a_protective_schemehttp://www.electrical-installation.org/enwiki/Practical_values_for_a_protective_schemehttp://www.electrical-installation.org/enwiki/Location_of_protective_deviceshttp://www.electrical-installation.org/enwiki/Location_of_protective_deviceshttp://www.electrical-installation.org/enwiki/Conductors_in_parallelhttp://www.electrical-installation.org/enwiki/Conductors_in_parallelhttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/General_method_for_cable_sizinghttp://www.electrical-installation.org/enwiki/General_method_for_cable_sizinghttp://www.electrical-installation.org/enwiki/Recommended_simplified_approach_for_cable_sizinghttp://www.electrical-installation.org/enwiki/Recommended_simplified_approach_for_cable_sizinghttp://www.electrical-installation.org/enwiki/Busbar_trunking_systemshttp://www.electrical-installation.org/enwiki/Busbar_trunking_systemshttp://www.electrical-installation.org/enwiki/Determination_of_voltage_drophttp://www.electrical-installation.org/enwiki/Determination_of_voltage_drophttp://www.electrical-installation.org/enwiki/Maximum_voltage_drop_limithttp://www.electrical-installation.org/enwiki/Maximum_voltage_drop_limithttp://www.electrical-installation.org/enwiki/Calculation_of_voltage_drop_in_steady_load_conditionshttp://www.electrical-installation.org/enwiki/Calculation_of_voltage_drop_in_steady_load_conditionshttp://www.electrical-installation.org/enwiki/Short-circuit_currenthttp://www.electrical-installation.org/enwiki/Short-circuit_currenthttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/3-phase_short-circuit_current_(Isc)_at_any_point_within_a_LV_installationhttp://www.electrical-installation.org/enwiki/3-phase_short-circuit_current_(Isc)_at_any_point_within_a_LV_installationhttp://www.electrical-installation.org/enwiki/Isc_at_the_receiving_end_of_a_feeder_as_a_function_of_the_Isc_at_its_sending_endhttp://www.electrical-installation.org/enwiki/Isc_at_the_receiving_end_of_a_feeder_as_a_function_of_the_Isc_at_its_sending_endhttp://www.electrical-installation.org/enwiki/Particular_cases_of_short-circuit_currenthttp://www.electrical-installation.org/enwiki/Particular_cases_of_short-circuit_currenthttp://www.electrical-installation.org/enwiki/Calculation_of_minimum_levels_of_short-circuit_currenthttp://www.electrical-installation.org/enwiki/Calculation_of_minimum_levels_of_short-circuit_currenthttp://www.electrical-installation.org/enwiki/Verification_of_the_withstand_capabilities_of_cables_under_short-circuit_conditionshttp://www.electrical-installation.org/enwiki/Verification_of_the_withstand_capabilities_of_cables_under_short-circuit_conditionshttp://www.electrical-installation.org/enwiki/Protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Connection_and_choice_for_protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Connection_and_choice_for_protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Sizing_of_protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Sizing_of_protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Equipotential_conductorhttp://www.electrical-installation.org/enwiki/Equipotential_conductorhttp://www.electrical-installation.org/enwiki/The_neutral_conductorhttp://www.electrical-installation.org/enwiki/The_neutral_conductorhttp://www.electrical-installation.org/enwiki/Sizing_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Sizing_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Protection_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Protection_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Breaking_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Breaking_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Isolation_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Isolation_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Isolation_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Breaking_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Protection_of_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/Sizing_the_neutral_conductorhttp://www.electrical-installation.org/enwiki/The_neutral_conductorhttp://www.electrical-installation.org/enwiki/Equipotential_conductorhttp://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Protective_conductor_between_MV/LV_transformer_and_the_main_general_distribution_board_(MGDB)http://www.electrical-installation.org/enwiki/Sizing_of_protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Connection_and_choice_for_protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Protective_earthing_conductorhttp://www.electrical-installation.org/enwiki/Verification_of_the_withstand_capabilities_of_cables_under_short-circuit_conditionshttp://www.electrical-installation.org/enwiki/Calculation_of_minimum_levels_of_short-circuit_currenthttp://www.electrical-installation.org/enwiki/Particular_cases_of_short-circuit_currenthttp://www.electrical-installation.org/enwiki/Isc_at_the_receiving_end_of_a_feeder_as_a_function_of_the_Isc_at_its_sending_endhttp://www.electrical-installation.org/enwiki/3-phase_short-circuit_current_(Isc)_at_any_point_within_a_LV_installationhttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/Short-circuit_current_at_the_secondary_terminals_of_a_MV/LV_distribution_transformerhttp://www.electrical-installation.org/enwiki/Short-circuit_currenthttp://www.electrical-installation.org/enwiki/Calculation_of_voltage_drop_in_steady_load_conditionshttp://www.electrical-installation.org/enwiki/Maximum_voltage_drop_limithttp://www.electrical-installation.org/enwiki/Determination_of_voltage_drophttp://www.electrical-installation.org/enwiki/Busbar_trunking_systemshttp://www.electrical-installation.org/enwiki/Recommended_simplified_approach_for_cable_sizinghttp://www.electrical-installation.org/enwiki/General_method_for_cable_sizinghttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/Practical_method_for_determining_the_smallest_allowable_cross-sectional_area_of_circuit_conductorshttp://www.electrical-installation.org/enwiki/Conductors_in_parallelhttp://www.electrical-installation.org/enwiki/Location_of_protective_deviceshttp://www.electrical-installation.org/enwiki/Practical_values_for_a_protective_schemehttp://www.electrical-installation.org/enwiki/Overcurrent_protection_principleshttp://www.electrical-installation.org/enwiki/Conductor_sizing_and_protection
7/27/2019 Module 7 Assignment Info
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BY its very nature, electricity is as dangerous a substance
as
anyone can work with. When adjacent cables carrying three-
phase power currents suffer a short circuit fault, the
inducedmagnetic fields result in the cables experiencing
significant
opposing forces. If the cables are incorrectly or poorly
restrained, the opposing forces can free them from their
restraints, resulting in costly damage to cables and cable
management systems; it can also result in expensive
production
down time and risk to life.
A video showing the dramatic, damaging effects of short
circuitfaults is available from IPD Industrial Products. In
addition to
the possible risks of short circuit faults, the video also
illustrates the extensive testing done by the company to
ensure
complete protection from faults.
Cable cleats are designed to fix, retain and support cables.
Correctly selected and applied cleats will contain cables in
the
event of a fault, and will enable the circuit to be restored
oncethe fault has been repaired.
Selection of a correct cleat begins during the design of a
project:
the force between cables is calculated to determine the
cleat
type and strength required. A number of other factors then
need to be taken into account, including physical
performance,
mounting surface, installation space and
the environment in which the installation will operate. Onlywhen
these have all been considered can a project designer be
confident in specifying the correct cleats for an
installation.
The recent introduction of IEC61914:2009 Cable Cleats for
Electrical Installations was a huge boost for Ellis Patents,
the
world-leading manufacturer of cable cleats. The companys
products are used extensively in offshore and onshore
environments and all are comprehensively tested and
certified
by third parties.
