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 perform either on-delay or off-delay… 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 4. IR Value for Electric… 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 customer acceptance test, with minimum… 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 adequate power capacity with proper… 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 accumulation of dirtiness in lamps,… 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 flow, we employ different types… 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 of heating the transformer? Responsible… 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. Transducers also isolate and buffer… 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 and the effect of arcing… 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 carrying capacity it is simply… 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 the worker to the flash… 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 and sophisticated systems and equipment… 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 starting current surges. To limit… 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 resistance, a voltage drop is… 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, marine applications, material handling, paper,… Read more
Apr 05, 2012 | Edvard
