On-off controllers are normally used for low loads temperature changes flow rate

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Question
On-off controllers are normally used for
Options
A. low loads
B. temperature changes
C. flow rate changes
D. none of these

Correct Answer

low loads

Process Control and Instrumentation problems

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3. A process is initially at steady state with its output y=l for an input u=l. The input is suddenly changed to 2 at time t=0. The output response is y(t)=1+2t. The transfer function of the process is
Options
A. 2/s
B.
C.
D.

5. "A control system is unstable, if the open loop frequency response exhibits an amplitude ratio exceeding unity at the crossover frequency." This is __________ criterion.
Options
A. Bode stability
B. Nyquist
C. Routh stability
D. none of these

7. For increased speed of response of an expansion pressure spring thermometer, the thermometer bulb should have a
Options
A. large area but small mass.
B. high thermal conductivity.
C. small specific heat.
D. all'a', 'b' & 'c'.

9. For the block diagram shown below :

The characteristic equation is
Options
A. ?_l S (?_ps + 1) + K_c . K_p (?_lS + 1) e^{-?_d s} = 0
B. (?_mS + 1) (?_pS + 1) + K_m . K_p e^{-?_d S} = 0
C. ?_l S(?_m S + 1) (?_p S + 1) +K_c . K_p . K_m (?_l s + 1) e-?_dS = 0
D. (?_ms + 1) (?_p s + 1) + K_c . K_p . K_m . e^-?_dS = 0

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