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Showing posts with the label Electrical & Instrumentation

Chain conveyor troubleshoot guide

  Problem Identification & Corrective Action Sl No. Problem Potential Cause Solution 1 Chain rises off from sprocket 1.Excess chain slack. 2.Excess wear at the bases of sprocket teeth. 3.Excess chain extension. 4.Foreign material stuck to the bases of sprocket teeth. 5.Reverse rotation of conveyor 6.Uneven chain tightening of chain 1.Adjust the amount of slack equally at both sides. 2.Carryout hard facing of the sprockets 3.Replace the elongated chain parts. 4.Remove the foreign material from the bases of the teeth. 5.Avoid reverse rotation of the conveyor when chain tightened is uneven 2 Chain separates poorly from the sprocket. 1.Sprocket misalignment. 2.Excess chain slack. 3.Excess wear at the bases of sprocket teeth. 4.Uneven chain tightening of chain 1-Adjust alignment. 2-Adjust the amount of slack.

Questions & Answers on Power Transformers

    1-What do you mean by power transformer? It is a static Electro-magnetic machine which transforms alternating current from one AC voltage to another AC voltage at same frequency & at the same apparent power (KVA). 2-What is the principle of Power transformer operation? Power transformers work on the principle of electromagnetic induction. Which states that, EMF induced in a closed conducting circuit when the magnetic flux linking with that circuit changes in time. 3-What is the main function of a power transformer? Generally it is used for stepping up or stepping down of Voltage to desired level 4-What are the various parts of power transformer? General arrangement of Power Transformer Casing Core Primary & secondary windings LV & HV bushings Radiators & cooling system Conservator Breather Protection devices like Buchholz relay, relief valves, temperature sensors 5-Why does the oil conservator is placed at higher elevation? Oil conservator is placed at a slightly hi

Batteries & troubleshooting

   1-List down the applications of auxiliary DC power supply system in Power plants?   Protections relays Circuit breakers DCS Trip circuits Signaling Telephone system & communication Emergency lighting Transmitters & Positioners Emergency oil pumps Metering panels 2-List down the various DC voltages & their applications in power plants Sl No. Voltage Applications 1 220 VDC & 110 VDC Protection system Emergency lighting Trip & closing coil of circuit breakers Operating mechanisms 2 48 VDC Telephone communication 3 +/- 24 VDC Control circuits Measuring instruments Static relays 3-What is the power source for DC supply? Main power source is lead-acid storage battery & AC/DC rectifier set 4-What are the installation requirements for lead acid battery ? The room should be isolated from other system Room should have adequate lighting & venti

Questions Answers on basics of instrumentations for Power plant Mechanical Engineers

1. What is an instrumentation? Instrumentation is the art of measuring a value of plant parameters. Or The technology which is used to measure and control the process system of plant is called instrumentation. 2. What is an instrument? An instrument is a device that transforms a physical variable of interest (the measurand) into a form that is suitable for recording (the measurement). 3. What is measurand? A physical quantity, property, or condition being measured. Often, it is referred to as a measured value. 4. What is a sensor? The portion of a measurement system that responds directly to the physical variable being measured. 5. What are the various variables measured in a power plant? Pressure, temperature, force, speed, frequency, current, voltage, resistance, time, displacement, acceleration, light intensity, density, pH, conductivity, flow etc. 6. What is calibration of a sensor? The relationship between the physical measurement variable input and the
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