1. When does the Proportional (P) Controller is used? Answer. Proportional (P) Controller is used during the following conditions: Load Changes are small Offset (error exist due to difference between steady state value and desired value) can be tolerated. The process reaction rate is such as to permit a narrow proportional band. Since this reduces … Read more
Usage of Single Computer for control of all the process variables of a plant would result in the loss of control activities in the plant if a failure occurs in the master single computer. Also, the time required for accessing large data, processing the received data and controlling of the entire plant by single computer … Read more
Question: What is a Circuit Breaker? Answer. Circuit Breaker is a mechanical device designed to close or open contact members, thus closing or opening an electrical circuit under the normal or abnormal conditions. Question: How does a Circuit Breaker different from Switch? Answer. A switch is just a device when can be able to open and close … Read more
Air Blast Circuit Breaker is those kind of circuit breaker which operates in air at pressure of 20-30 kg/cm2. It is also good choice to avoid the risk of oil fire, in case of oil circuit breaker. The aim of all kind of circuit breaker is to prevent the re-establishment of arc after current zero by creating … Read more
What are Valve Regulated Lead Acid (VRLA) Batteries? These batteries are popularly termed as maintenance free lead-acid batteries. Each cell in VRLA battery will have a value (automating operating) to allow the gas to escape if developed by the overcharging the cells and to hinder the entrance of oxygen from the air into the cell. … Read more
Definition A generating station which utilizes the potential energy of water at a high level for the generation of electrical energy is known as a hydro-electric power station. Hydro-electric power stations are generally located in hilly areas where dams can be built conveniently and large water reservoirs can be obtained. In a hydro-electric power station, … Read more
A generating station in which nuclear energy is converted into electrical energy is known as a nuclear power station. In a nuclear power station, heavy elements such as Uranium (U235) or Thorium (Th232) are subjected to nuclear fission. in a special apparatus known as a reactor. The heat energy thus released is utilized in raising … Read more
A generating station in which diesel engine is used as the prime mover for the generation of electrical energy is known as diesel power plant or diesel power station. In a diesel power plant, a diesel engine is used as the prime mover. The diesel burns inside the engine and the products of this combustion … Read more
Q. What is meant by “energy loss” in a machine? Answer. Whole of the input energy to the electrical machine is not converted into useful output energy but a part of the energy is converted into heat and is lost for the useful purpose of the machine. The energy converted into heat is called the … Read more
Q. What are the requirements of good electric braking? Answer. The requirements of good electric braking are: (i) The braking should be quick and reliable in action. (ii) The braking must be controllable. (iii) Some suitable means must be provided for dissipation of kinetic energy of the moving parts of the motor and its driven … Read more
