Electric Motor
Ten different duty types (load cycle) of a three-phase asynchronous motor
The term duty defines the load cycle to which the machine is subjected, including, if applicable, starting, electric braking, no-load, and rest de-energized periods, and including their durations and sequence… Read more
Dec 11, 2017 | By Edvard
Electric Motor
Practical Basics Of Synchronous Motors That Every Electrical Engineer Should Know
Like the asynchronous motor, the synchronous motor consists of a stator and a rotor separated by the air gap. It differs from the asynchronous motor in that the flux in… Read more
Nov 08, 2017 | By Edvard
Electric Motor
How bad harmonics influence the work of motors and generators, transformers, capacitors etc.
The distortion in the waveform in the load current of any nonlinear device causes similar changes in the voltage waveform relative to the harmonic impedance of the source network. This… Read more
Oct 25, 2017 | By Edvard
Electric Motor
Troubleshooting three basic hardwired control circuits used in starting electric motor
Generally speaking, basic control circuits are used in starting, stopping, sequencing, and safety automatic interlocking of equipment and machines. The control circuit consists of relays, relay contacts, contactors, timers, counters,… Read more
Oct 23, 2017 | By Edvard
Electric Motor
Specific capacitor installations & reactive compensation of asynchronous motors / transformers
Although in general, the calculation of the reactive power to be installed is initially carried out globally, it is advisable not to be swayed by the apparent simplicity of this… Read more
Aug 30, 2017 | By Edvard
Electric Motor
Recommended maintenance practice for electric motors and generators
Motors are inherently highly reliable, requiring little routine maintenance. This remains true for most duties but may not be so where environmental conditions are aggressive, the starting duty is onerous,… Read more
May 25, 2017 | By Edvard
Electric Motor
Selecting the suitable frequency converter and motor for these 3 applications
The motor is selected according to the basic information about the process. Speed range, torque curves, ventilation method and motor loadability give guidelines for motor selection. Often it is worth… Read more
May 24, 2017 | By Edvard
Electric Motor
Why overmotoring an application is not such a good idea
In many instances, the practice has been to overmotor an application, i.e., to select a higher-horsepower motor than necessary. The disadvantages of this practice are: Lower efficiency Lower power factor… Read more
Mar 13, 2017 | By Edvard
Electric Motor
The essentials of synchronous machines in power distribution networks
Synchronous machines can be used as generators or motors. They are of 3-phase construction, even though some special exceptions can be found. A bulk of the applications are within power… Read more
Mar 06, 2017 | By Edvard
Electric Motor
Basic electrical design of a PLC panel (Wiring diagrams)
It is uncommon for engineers to build their own PLC panel designs (but not impossible of course). For example, once the electrical designs are complete, they must be built by… Read more
Feb 27, 2017 | By Edvard
Electric Motor
Detailed calculation of currents and power according to the type of load
Currents and power analysis are key factors in any design or redesign of an installation they will enable the source(s) to be sized according to the purpose of the installation,… Read more
Feb 13, 2017 | By Edvard
Electric Motor
Practical checks for motor selection on AC adjustable speed drive systems
Important checks to consider in the motor selection for AC adjustable speed drive system: Determine motor enclosure requirements Determine motor torque and speed requirements: Operating speed range Breakaway torque Determine… Read more
Feb 10, 2017 | By Edvard
Electric Motor
Ladder logic for special motor control circuits – jogging and plugging
Ladder logic is often used to implement various motor control circuits. Beside standard motor control circuits, there are also special control circuits designed to allow jogging (brief energization of the… Read more
Feb 01, 2017 | By Edvard
Electric Motor
The influence of voltage unbalance on NEMA motor performance
Voltage unbalance can be more detrimental than voltage variation to motor performance and motor life. When the line voltages applied to a polyphase induction motor are not equal in magnitude… Read more
Jan 27, 2017 | By Edvard
Electric Motor
Main features that make AC drive the leading motor control method
We can confidently say that the AC drive is the leading motor control method. This technical article deals with a closer look at the different features of the AC drive, and… Read more
Dec 23, 2016 | By Edvard
