Battery systems

Batteries is one of the common thing in our daily application.We used it for domestic and industrial application.It can stored the electricity energy to made our equipment function properly.

We need to choose the suitable type of battery system depend on our application and design to ensure it can operated with maximum capacity.It have in several type such as dry type and wet types with different ampere rating from low to high current capacity.

In the market now we can selected several type of system for battery can suit for our needed and design.Below i listed basic categories for battery system read more

Safety precaution for electrical works

As we known when working on electrical installations, safety matter is our priority.Every step we need to consider about hazards when perform electrical works.

Only competent electrician can work on electrical installation or live condition according to relevant industrial safety standards.Common industrial safety standard for electrical works such as VDE 0105 for Germany, and international standards for EN 50110 or IEC 60364.

For electrician,they need to special tools which have been tested and qualified with electrical standard.Hand tools also must suitable and followed the electrical standard  IEC 60900 and it has specified worldwide requirements for tools for electrical live condition.

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How calculate ampere for electric motor?

Generally for electric motor size,it rated by horsepower (hp) or kilowatts (kW) unit.We can recognize the electric motor size when refer to their kilowatts or horsepower.So from power (kW/hp), how we can know the full load ampere for electric motor?

This time i want share about how to calculated the full load ampere (FLA) of electric motor from their power rated.It not difficult if we know the right formula to get the answer.From this calculation we only can estimate the value of full load ampere.

We cannot get the actual full load ampere because it depend on efficiency of motor.If electric motors have a higher efficiency rating,it will draw fewer amps, for example a 10 HP motor with a 60% efficiency rating will draw about 65 amps at 230 VAC compared to about 45 amps for a motor with a 80% rating. read more

Vacuum circuit breaker

As we know vacuum mean the the pressure is maintained below atmospheric pressure( unit : mm Hg ).So the manufacture made a research and development to design the vacuum circuit breaker based on current cannot jump in vacuum condition.

Vacuum Circuit Breaker used the vacuum pressured to extinguish the current arc when it switching.Normally this type of circuit breaker used for medium voltage ( 1 – 35 kV ) power supply.The ampere rating for vacuum circuit breaker is until 3000 ampere.

Vacuum Circuit Breaker have a  high insulating strength and capable to extinguish the current arc for medium voltage power supply.It more safe for switching and environment friendly.It only a vacuum atmosphere. read more

Criteria for cable design

Cable is a important thing in electrical engineering to transfer the power supply from distribution to end user or equipment.It must have a quality and durability to ensure it can stand for any condition and long life span.

Day by day,manufacture made the research and development to improved quality and design of cable suitable with new technology and different surrounding area.It also improved for more efficiency,low cost,heavy duty and environment friendly.

To make a proper design for electric cable,the major criteria to get electrical cable be the good design and high quality are 4 items following : read more

NEC calculation for overload sizing

Sizing for overload is important to avoid serious damage for electrical application such as motor starter,machinery or others electrical equipment.

According to NEC,the general requirement for overload sizing be set around 115% or 125% from full load ampere.We should setting the overload relay within this parameter to avoid electric motor from serious damage.

For calculation of overload sizing,it depend on the motor full load ampere current rating,the service factor and temperature for motor.I already explain in my last post about several factor effected for overload relay sizing. read more

UPS batteries charging rates

Basically charging rates for UPS batteries depend on type of batteries cell such as Lead-acid (Pb) or Nickel Cadmium (NiCd).This two types of batteries cell have a different method to charging up.

For Lead-acid (Pb) cells is used a ‘constant voltage’ method.It mean where the current varies as the state of charge changes.Different method for Nickel Cadmium (NiCd) cells,it  is used ‘constant current’ where the cell voltage varies as the state of charge changes.

When we try to charging batteries  from  Lead-acid (Pb) cells type,the basic process are from a constant voltage source the charging current starts high and slowly decreases to a constant value when the cells become fully charged.The constancy of the current is an approximate indication that the cells are fully charged. read more