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Refer to the circuit shown in Figure 27–2. Would it be possible to replace the hand-off-auto switch in this circuit with a hand-off-auto switch that contained a common terminal and center Off position like the HOA switch shown in Figure 27–1? Explain your answer.
Whether it is possible to replace the hand off auto switch in the circuit with the hand off auto switch that contains the common terminal and center off position like the HOA switch shown in the Figure 27-1.
Explanation of Solution
Refer to the Figure 27-1
Consider that the motor is controlled by the hand off automatic switch. In case the position of the contact is at the center off then the motor stops to work.
Refer to the Figure 27-2
Consider both the switch contains the hand off and the automatic switch to control the fan that pulls the air through the building. In that case the switch is same as of Figure 27-1
As both the switch has Hand off and the automatic position the switch contains the two sets of the contacts one is 1-2 and the other is 3-4. In case the set is in hand position then the connection is made in between the contacts terminal 1 and 2 and in case the set is in automatic position the connection is made between the 3-4 terminals and when the set is off no connection is made in between the terminals.
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Chapter 27 Solutions
Industrial Motor Control
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