How to choose speed controllers for AC motor?

Now around the world are using the speed controllers to control and drive their electric motor such as frequency inverter and soft starter.This speed control get a good reputation to reduce electricity cost and high efficiency to drive electric motor.

Speed controller is low maintenance and have a long life span.It easy to install and user friendly to setup and setting the parameter.

The wiring for power supply and control circuit is not so complicated like conventional motor control.This post i want share some basic aspects for choose the suitable ac motor speed controller that we must consider when to buy or install it on our application.I hope this information can be the basic guideline. read more

Maintenance for low voltage circuit breakers

Low circuit breaker normally operating at 600 volt AC and below.The common used types of  circuit breaker around the world such as molded case circuit breaker (MCCB) and Air circuit breaker ( ACB ).

This low voltage circuit breaker usually used for power distribution and sub power distribution at factory and general industry.It a combination with electrical and mechanical device to protect our electrical system from overload and over current matters.

IEE regulation stated a several condition for maintenance and services for circuit breaker.The main purpose is to make sure this circuit breaker in good condition and can activated when problem happen.It also for safety purpose for equipment and personnel. read more

Class of insulation

The main component for electric motor is a stator.What is stator?Basically stators are wound with insulated windings made from cooper wire.The insulation  materials for winding of stator such as polyester, poly vinyl formal,polyurethane etc.

The main purpose of insulation is to protect the windings in the slots of the stator lamination and layer between winding coils.The insulation class is durability factor depend on whole of insulation condition.

According from IEEE regulation,The classification of insulation electric motor have a deference rating for maximum temperature that insulation winding can operate.We can see the insulation class at  motor nameplate.Please refer the table below for insulation class rating temperature. read more

Auto transformer

This is a one from several types of transformer.It usually used for motor starter,we recognize it by name “auto transformer starter”.Basically design for auto transformer only have a single winding and provided with tap connection for step up or down.

It have magnetic core with single winding which common primary and secondary circuits.The primary connection is connected with main AC power supply and secondary connection is connected with load.

If the primary is the total winding and is connected to a supply and the secondary circuit is connected across only a portion of the winding,It mean this is for stepped down voltage. read more


Relays have a wide range of application in industry.Even with the advent of electronic control such as PLC and other solid state devices such as thyristors,the electromechanical relay still retain a high level of acceptance.

We can found relay in every where such as control panel,equipment and machinery.It is common use for automation and motor control application.

The reason for this is that for simple types of control,relay offer a cost effective solution.They are available in a large range of configurations from small of only 10mm in length with multiple contact pair for data communication,to large relay called contactor for carrying heavy current loads in applications such as switching 3 phase motors. read more

PLC Programming

How we can make the PLC functioning properly to control the machine?We need to stored the PROGRAMMABLE CONTROL SYSTEM  into the PLC memory.We need the special PLC PROGRAM to written the PLC language.For that task..we need the PC or LAPTOP to run the programming software :D

After we make a sketch for the diagram control circuit,we need to transfer into the Programming Language using the special software provide by PLC maker. This a the best part when we need to draw the diagram into the program.We need study the user manual first before can done properly :D

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Residual Current Circuit Breaker

This device is important in electrical wiring installation.It is a life guard device to protect from electric shock.Others circuit breaker only can detect the fault from over current and short circuit but cannot detect the current leakage.

That why RCCB is very important.Only this device can detect the current leakage.The current leakage can cause the injury or dead for human and can lead to fire hazard.When design the distribution panel board,please make sure this device include in our planning to for consumer safety and avoid equipment from damage. read more