ESE ECE Prelims case studies
ESE ECE Prelims · Put your knowledge to work in context.
The ESE ECE Prelims is the screening stage of India's Engineering Services Examination for Electronics and Communication Engineering candidates, run by the Union Public Service Commission. Clearing it is the gateway to the ECE main papers and, ultimately, to central government engineering posts such as those in the Indian Telecommunication Service, the Central Power Engineering Service and related departments. The ESE ECE Prelims case studies are 5 cases and about 4,581 words.
1Series RLC Ringing That Does Not Match the Component Values
A final-year lab group characterises a series RLC low-pass network on a breadboard: L = 10.0 mH (toroidal choke, DC resistance measured on a bench DMM as 12 Ω), C = 1.5 µF metallised polypropylene, and an external 47 Ω carbon-film resistor. The network is driven from a unity-gain power op-amp buffer whose output resistance is below 0.5 Ω, so the source is effectively ideal.
866 words, about 4 min2Strain-Gauge Channel: Is It Resolution or Interference?
A production test rig measures strain with a 350 Ω foil bridge energised from a 5.000 V reference. The bridge is rated 2.00 mV/V, so full-scale differential output is 10.0 mV.
1,003 words, about 5 min3A 2.4 GHz Backhaul Link That Underperforms Its Budget
A utility is commissioning a 5 km point-to-point link at 2.4 GHz between a substation and a control building. The transmitter delivers 20 dBm into a 2 dB feeder; the transmit antenna has 6 dBi gain.
906 words, about 5 min4A Positioning Loop That Overshoots After the PLC Was Added
A machine-tool axis uses a DC servo with a current-mode drive, a 1000-line incremental encoder and a PLC-based position loop. From the command to the encoder output, the axis behaves as G(s) = K / (s(1 + 0.1s)) with K = 20 s⁻¹ - the product of motor gain, encoder scaling and proportional controller gain.
895 words, about 4 min5Two-Wattmeter Method with a Backward Deflection
A technician commissions a 7.5 kW, 415 V, 50 Hz, 4-pole cage induction motor using the two-wattmeter method with two 5 A, 150 V dynamometer wattmeters connected directly in the lines, with no CTs or PTs. At the measured shaft load, wattmeter 1 reads 1.9 kW.
911 words, about 5 min