Electrical Lectures
What is the complex power and how it figures in power analysis
Considerable effort has been expended over the years to express power relations as simply as possible. Power engineers have coined the term complex power, which they use to find the total effect of parallel loads. Complex power is important in… Read more
Mar 17, 2017 | By Edvard Csanyi
Industrial Automation
PLC power supply and safety (emergency) circuits requirements
The source for a PLC power supply is generally single-phase and 120 or 240 VAC. If the controller is installed in an enclosure, the two power leads (L1 hot and L2 common) normally enter the enclosure through the top part… Read more
Mar 15, 2017 | By Edvard Csanyi
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 Higher motor cost Higher controller cost Higher installation costs Let’s… Read more
Mar 13, 2017 | By Edvard Csanyi
Energy and Power
Three performance factors you must consider when sizing batteries
Batteries need to be sized correctly to be able to feed the required load for the required time, and a number of factors need to be decided to be able to optimize the battery for the duty expected. Some of… Read more
Mar 10, 2017 | By Edvard Csanyi
Datacenters
Never underestimate electrostatic discharge (ESD) while working with data networking equipment
Let’s start with basics you probably already know, but nevertheless. It’s important to explain the basics first. Electrostatic Discharge (or ESD) refers to the transfer of electrostatic charge between bodies at varied voltages that is caused by direct contact or… Read more
Mar 08, 2017 | By Edvard Csanyi
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 ranges roughly varying from a megawatt level to several tenths… Read more
Mar 06, 2017 | By Edvard Csanyi
Electric Motor
Voltage drop calculation methods with examples explained in details
What we call “voltage drop” is really just the differential in voltage between where the installation started and where the receptor was connected. The primary concern with voltage drop is that, under steady-state conditions of typical load, the voltage at the… Read more
Mar 03, 2017 | By Edvard Csanyi
Maintenance
Performing power factor test on dry-type transformer during commissioning
The power factor test is a maintenance test used to determine the insulation system dielectric power loss by measuring the power angle between an applied AC voltage and the resultant current. Power factor is defined as the ratio of the… Read more
Mar 01, 2017 | By Edvard Csanyi
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 an electrician. Therefore, it is your responsibility to effectively communicate… Read more
Feb 27, 2017 | By Edvard Csanyi
Low Voltage
Measurement of N–PE loop resistance in TN, TT and IT systems
Up-to-date test instruments, with built in modern electronics, can measure loop resistance even between the neutral N and protection PE conductors in spite of possible high currents in the neutral conductor. The current, which is driven by phase voltages through… Read more
Feb 24, 2017 | By Edvard Csanyi
Energy and Power
Do you know what ground potential rise is? It’s really important.
First of all, ground potential rise is very important and very dangerous event. The grounding engineer will be required to develop safety systems to protect any personnel working where ground potential rise hazards are known to exist. Federal law mandates… Read more
Feb 22, 2017 | By Edvard Csanyi
Cables
Guidelines for high potential (Hi-Pot) DC testing of medium voltage cables
This technical article provides general guidelines for high potential “Hi-Pot” DC testing of MV power cables. All tests made following cable installation and during the warranty period must be performed in accordance with the applicable specifications. Testing should be performed… Read more
Feb 20, 2017 | By Edvard Csanyi
Energy and Power
5 good examples of locking out HV/MV/LV structures and equipment
In all cases the choice of locks and safety positions requires prior analysis of the locking sequence to be applied in order to correctly define the requirement and clearly identify the related risks. Remember that “electric” locking systems are never… Read more
Feb 17, 2017 | By Edvard Csanyi
Energy and Power
How a three-phase power transformer responds to harmonics
The way in which a three-phase transformer responds to harmonics depends on the connection configuration used. For a star-star configuration, any imbalance in the phase currents results in the star point being electrically displaced and the phase to neutral voltages… Read more
Feb 15, 2017 | By Edvard Csanyi
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, the intended use of the circuits and the receivers to… Read more
Feb 13, 2017 | By Edvard Csanyi
