Wire Gauge Size Chart AWG to mm2
AWG to mm2, Higher the AWG number, smaller the wire diameter.
AWG to mm2, Higher the AWG number, smaller the wire diameter.
Switchboard ASSEMBLY Base Frame Provides Base support to Assembly structure and evenly pass load onto base concrete foundation.
Busbar used in Switchboard Assemblies are Al or Cu, they have specific Weight basis size and Density of Atoms for given volume.
Metals used in Switchboard Assemblies are CRCA, Al, Cu, etc have specific Weight basis its Density of Atoms for given volume.
Galvanization is the process of applying Zinc coating on Steel to prevent Corrosion. In Hot dip Galvanization, Fabrication is submerged in Molten Zinc.
Sheet Metal for ASSEMBLY Enclosure are carefully selected considering Sheet thickness, Density and Melting point.
Metalic sheets used for ASSEMBLY Enclosures, need to be Surface treated to provide Corrosion resistance. GI, CRCA, Galvanization, Zinc..
Motor contribution is the Current feed back by Motor, due to rotating magnetic fied in rotor, into System during short circuit condition.
Electrical joints of Dissimilar metals – Aluminium and Copper suffer from Galvanic Corrosion and thermal expansion effects.
Coefficient of Thermal Expansion is the rate of change of unit Length/Volume per unit degree change in temperature.
Arc flash occurs when electrical current becomes uncontrolled, results in release of energy that ionizes air, releasing enormous heat, light, sound.
Lightning is electrostatic discharge, causing the instantaneous release of energy. SPD diverts surge to ground without impacting utility supply.
Short-Circuit fault allows the current to flow through unintended path with very low impedance, which results into excessive current flow through the path.
Highest Prospective Short Circuit Current which a typical Generator can feed in case of of Short Circuit fault for Individual and Multiple Generators.
Typical safe ability of Transformer, Generator and Cable to withstand Isc – short circuit fault current in multiple of its In – rated current, without damage to the equipment.
Highest Prospective Short Circuit Current Isc which a typical oil immersced Transformer can feed in case of of Short Circuit fault is Isc of Transformer.
Steps and Limits of Temperature rise of ASSEMBLY, Verification by Testing with Current, with Arrangement as in normal use.
In Powder coating process, CRCA surface is given Anti Corrosive Surface treatment, then Epoxy Powder is applied, melted and hardened.
While commissioning Assembly, Switchgear Nameplate gives important information, characteristics, Energy, Short Circuit, Accordingly Safety can be ensured.
I2t – Let through Energy is available thermal energy resulting from Current Flow during circuit opening in Fuse, MCCB, MCB.Unit is A2S (Ampere2 Second)
I2t – Let through Energy is available thermal energy resulting from Current Flow during circuit opening. I2t (of circuit breaker) < K2S2 (of cable)
Unbalanced 3 phase system can be resolved into 3 balanced systems – Positive, Negative and Zero Sequence Symmetrical components.
Electrical Panel Assemblies needs good understanding of GAS laws, PV=nRT, which relates Pressure, Volume, Temperature and Amount of GAS inside the ASSEMBLY.
Heat is a flow of energy from higher temperature object to lower temperature object. Heat transfer continues until two objects reaches thermal equilibrium.
Nonconducting material that provides electric isolation of two parts at different voltages.
It must have an electrical resistivity and a dielectric strength sufficiently high for the given application.
The secondary requirements relate to thermal and mechanical properties.
Solar Radiation is electromagnetic radiation emitted by the Sun. Solar Gain is the Increase in Thermal Energy of a Object as it absorbs Solar Radiation.
Severity Test for Assembly is Degree of impact a defect has on its operation, under conditions of high humidity combined with cyclic changes in temperature.
Mechanical properties of fasteners made of carbon steel and alloy steel ISO 898, with respect to Bolt class, Bolt Material, Proof Strength, Tensile Strength
Maximmum allowed Temperature on Busbar length and Joints-connection for Aluminium or Copper Busbar material considering Coating type.
CTI is max voltage which material can withstands 50 water drops without without formation of conductive path.
Clearance is the shortest distance in air between two conductive parts. Minimum Clearance required to withstand transient overvoltages as per IEC 61439.
Arc Flash is light and heat produced as a result of Arc Fault, due to low impedance path, which causes electrical explosion or discharge.
Arcing Class A, B, C according to personal protection from ASSEMBLY under Arc Fault and ASSEMBLY protection from internal Arc fault.
Tested Assemblies Varification Tests as per IEC 61439. Verification by TESTING, CALCULATION, DESIGN-RULES for Construction and Performance of ASSEMBLY.
Pollution factor can be solid, liquid, gaseous foreign matter which may reduce the dielectric strength accordingly Pollution Degree defined IEC 60664.
Circuit Breaker with Short Time withstand Icw capacity are Calassified as Category B (eg. ACB), and without Icw are Category A (eg. MCCB, MCB).
Clearance is shortest distance in air and Creepage is shortest distance along the surface of a solid insulating material, between two conductive parts.
Rated Impulse Voltage (Uimp) for Overvoltage category — I, II, III, IV at various nominal Voltage (Ue) is suggested in IEC 60664.
K factor of transformer is its ability to serve the nonlinear loads without temperature rise, Higher the K-factor greater the capacity to withstand harmonic heating effects.
IEC 60947 the Standard for Low Voltage Switchgear and Controlgear – ACB, MCCB, SDF, MCB, Contactor, Relay, Transfer Switch, Arc Quenching Devices.
IEC 61439, Low Voltage Power Switchgear and Controlgear ASSEMBLIES. Discrimination between TTA and PTTA eliminated by verification approach.
In Practice there wiill always difference in phase displacement between primary and secondary currents, Allowed limits are defined in IEC 61869-2.
Current transformer Accuracy class is highest permissible percentage error at rated current for that accuracy class, as per IEC 61869-2 and IS 2705.
Types of Fuse Link IEC 60269, gG, gM, gR, gS, gD, gN. HRC Fuse, Semiconductor Fuse.
Thermal Memory of CB remembers previous fault, till conductor cools – comes to Ambient temperature, if CB is closed before this it will to trip CB faster.
Temperature rise is defined as the average temperature rise of the ASSEMBLY above the Ambient Air Temperature, with Rated Current load for 8 hours.
Reference Ambient Air Temperature is one third (1/3) of sum of Maximum Air Temperature “Current + Daily Average + Annual Average + 10°C”. As per IS 9676.
Internal Arc Protection ensures Personal and ASSEMBLY protection under arcing conditions due to low impedance path, cause of electrical explosion.
Utilization Categories indicate the type of Load and Duty Cycle of the load basis which selection of Switchgear should be done for the intended application.
Utilization Categories indicate the type of Load and Duty Cycle of the load basis which selection of Switchgear should be done for the intended application.
ANSI standard Device Numbers and Acronyms, for Intelligent Electronic Device – IED Protection Relays / microprocessor based controllers / Numeric relay.
Protection degree provided by Assembly against mechnical impact, according to IEC 62262, is defined by IK code.
Protection degree provided by Assembly against ingress of solid foreign particals and liquid is indicated by the IP code.