Standard Temperature and Pressure Conditions
Standard temperature and pressure conditions as well as normal temperature and pressure conditions are used as reference points in thermodynamics of gases. Normally standard and normal temperature pressure conditions are…
Why have been limits imposed on the frequency ratio for thermowells?
In 1995, an accident caused due to breaking thermowells in Monju Nuclear Plant reactor, led to very serious damages to the surrounding facilities. Thermowells located on a line carrying liquid…
NFPA Standards (National Fire Protection Association Standards)
NFPA standards from National Fire Protection Association provide guidelines for incorporating fire protection safety measures in industrial systems. Classification of Fire and Hazard as per NFPAÂ - The National Fire Protection…
Motor Control Circuit Wiring
A simple three-phase, 480 volt AC motor-control circuit is shown here, both in pictorial and schematic form. This entire assembly consisting of contactor, overload block, control power transformer, power fuses…
Motor Protection Circuits
An essential component of any high-power motor control circuit is some device to detect a condition of excessive overload and interrupt power to the motor before thermal damage occurs. A…
Power Electronics Objective Questions
Power Electronics Objective Questions 1. Questions & Answers on Diodes The P-N Junction Power Diode - Part 1 Power Diode - Part 2 Types of Power Diodes - Part 1…
What is Contactor ?
To start up and shut down a three-phase AC induction motor, any three-pole switch with a suitable current rating will suffice. Simply closing such a switch to send three-phase power…
Solenoid Valve’s Energized or De-energized State ?
Solenoid valves may be used in such a way that they spend most of their time de-energized, energizing only for brief periods of time when some special function is required.…
What is a 4-way Solenoid Valve?
When a pneumatic actuator requires air pressure applied to two different ports in order to move two different directions (such as the case for cylinders lacking a return spring), the…
What is a 3-way Solenoid Valve ?
3-way solenoid valves operate in a manner analogous to single-pole double-throw (SPDT) electrical switches: with two paths for flow sharing one common terminal. 3-way solenoid valves have three ports for…
