Time relays setting ranges explained in details

Time relays are used in control switching operations involving time delay. Most of these time relays have multiple time setting ranges and most of them are explained below. Time relays… Read more

Apr 30, 2012 | Edvard

Measurement of insulation resistance (IR) – 2

Continued from first part: Measurement of insulation resistance (IR) – Part 1 1. IR Values For Electrical Apparatus & Systems 2. IR Value for Transformer 3. IR Value for Tap Changer… Read more

Apr 29, 2012 | jiguparmar

Measurement of insulation resistance (IR)

The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables. As a production test, this test is often used as a… Read more

Apr 28, 2012 | jiguparmar

Overview Of Electrical Loads In Building

The electrical design professional should determine a building’s electrical load characteristics early in the preliminary design stage of the building to select the proper power distribution system and equipment having… Read more

Apr 27, 2012 | Edvard

Light Emission Depreciation

Illuminance provided initially by a lighting installation will decrease in a gradual way during its use due to a reduction in lamp lumens, to lamps which burn down, and to… Read more

Apr 24, 2012 | Edvard

Direct On Line (DOL) Motor Starter

Different starting methods are employed for starting induction motors because Induction Motor draws more starting current during starting. To prevent damage to the windings due to the high starting current… Read more

Apr 22, 2012 | jiguparmar

What is the best transformer coolant?

One of the main sources of losses and reasons for temperature rise in various parts of a transformer are the magnetic circuit and windings. So what are the actually reasons… Read more

Apr 20, 2012 | Edvard

Analog Data Acquisition with Transducers

Transducers measure power system parameters by sampling instrument transformer secondaries. They provide a scaled, low-energy signal that represents a power system quantity that the SA interface controller can easily accept…. Read more

Apr 19, 2012 | Edvard

System protection and safety coordination definitions

The objective of system protection is to detect faults and to selectively isolate faulted parts of the system. It must also permit short clearance times to limit the fault power… Read more

Apr 16, 2012 | Edvard

Inspection Of Voltage Drop In Conductors

It is part of the inspection process to ensure that installed conductors have been correctly selected for current carrying capacity and voltage drop. To check the suitability of the current… Read more

Apr 15, 2012 | Edvard

What is incident energy caused by arc flash?

Incident energy is the energy per unit area received on a surface located a working distance away from the arc flash location. The working distance is the distance from where… Read more

Apr 13, 2012 | Edvard

Key Cyber Security Purposes for the Smart Grid

In the Smart Grid, there are two key purposes for cyber security: Keep electricity flowing to customers, businesses, and industry. For decades, the power system industry has been developing extensive… Read more

Apr 12, 2012 | Edvard

Star-delta motor starter explained in details

Most induction motors are started directly on line, but when very large motors are started that way, they cause a disturbance of voltage on the supply lines due to large… Read more

Apr 10, 2012 | jiguparmar

Short review of resistance, reactance and impedance

Resistance is essentially friction against the motion of electrons. It is present in all conductors to some extent (except superconductors!), most notably in resistors. When alternating current goes through a… Read more

Apr 08, 2012 | Edvard

The direct current (DC) motor – Principle of operation

DC motors have been used in industrial applications for years. Coupled with a DC drive, DC motors provide very precise control DC motors can be used with conveyors, elevators, extruders,… Read more

Apr 05, 2012 | Edvard