Electronics Paper 2, Nov/Dec. 2010

Questions:	1	2	3	4	5	6	7	8	9	10	Main

General Comments
Weakness/Remedies
Strength

Question 10
a) Explain the term open loop system. (b) Draw a block diagram of a negative feedback closed loop control system. (c) State two advantages of closed loop system over open loop system.
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OBSERVATION
The expected answers were: (a)An open loop system is one in which the desired output is set by means of an input signal, and it is assured that the output will remain at the desired level irrespective of variations either within the system or in the load or demand placed on the system. (b) Block diagram of a negative feedback closed loop control system (e)Two advantages of closed loop over open loop system: (i) stability in system operation; (ii)smooth system operation.