How to change rotation for Star Delta Starter?

15/08/2012 by 9 Comments

Electric motor have a two side of rotation.It is clockwise and anti clockwise or normally we call it forward and reverse rotation.An equipment or machinery that connected to electric motor have a rotation depend on manufacture design and application.

Common rotating equipment that we can found at our surrounding area such as pump,air-compressor,water jet and etc.Normally manufacture put a sign or arrow for rotation to avoid their equipment not install in proper way and can avoid serious damage or malfunction.

During installation and wiring termination,we must check and verify our rotation for equipment either it is forward or reverse rotation to avoid any problem or malfunction after completed installation works. read more

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The causes of electrical motor insulation failures

17/06/2012 by 1 Comment

Basically electrical motor have a phase to phase winding coil around armature to created a magnetic field.To avoid shortage between phase to phase winding,the insulation systems needed.

It consists of the groundwall insulation and turn to turn insulation. Typically for induction motor insulation is the slot of paper to protect between cooper and ground surface.For phase to phase insulation normally used sheet of insulation paper laid between phase. read more

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How calculate ampere for electric motor?

20/07/2011 by 75 Comments

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

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motor nameplate information #1 – Electrical Input

08/03/2011 by 8 Comments

The important information that we can see on motor nameplate is a electrical input.From this we can know what the voltage for motor,the suitable frequency,full load ampere,type of connection ( star or delta ),power factor and others.

We can collected the data for induction motor from name plate.This information is very important to troubleshooting or rectify any problem happen about that motor.

This information is critical items to ensure we install the right motor ans suitable with our application.Ok,i explain the detail about electrical input for induction motor that we can found on name plate. read more

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Miniature Circuit Breaker

03/09/2010 by 67 Comments

What is Miniature Circuit Breaker?

MCB (Miniature Circuit Breaker ( BS 3871 ) is a mechanical device operate automatic operation designed to connect and disconnect the electrical circuit in the ordinary and extraordinary situation.Suitable for AC and DC voltage.It mean main function is to protected equipment or circuit from overload and short circuit.

The size of MCB is small and usually use for household appliance and domestic.Average fix ampere rating from 6 Amp up to 125 Amp. It can be reset back to the normal condition after trip but cannot adjusted ampere rating.It can be found for single phase 1ø and three phase 3ø voltage power supply.

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