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Assignment No.2 09242020

Assignment No. 2
1. The circuit shown below is used for controlling furnace temperature. If the
pedestal voltage (i.e. voltage from Vp to ground in the figure), is zero, calculate the
firing angle, θ and the rms load voltage. If the pedestal voltage is equal to 3 V,
what is the new firing delay angle, θ?
2. Design the the circuit shown such that UJT will fire at 45° firing delay angle at the
given values of RT & CT . Based on your design, determine the voltage at the load for
a firing delay angle of 45°. Assume; UJT stand-off ratio is 0.63 and the AC line is 220
V, 50 Hz.