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How to stop motor m2 in this circuit?

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Newbie level 4
May 24, 2007
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hi there
i have uploaded a circuit there..
now i have to made many alteration in this circuit.

now consider another motor(M2) is just close to THERMISITOR R1

and if the temperature is increased by the motor(M2)..a fan is working on MOTOR(M1)
and i have to stop the first motor(m2) the same time...FAN is in working condition

please help me ..what i have to attached in this circuit
hope u reply

Re: please help

You posted the thread "How to stop motor" at for the same purpose?

And you want to switch on the m2 motor at the beginning, and then when the temperature raises high enough, the thermistor will switch on the fan motor m1 while switch off the m2, right?

Remember to use the thermistor of NTC type, not PTC, which resistance becomes smaller when temperature raises.

You just use 1 more p-n-p transistor as Q2, and call it Q3. Connect the E pin of Q3 to +12V, C pin of Q3 to M2 (just the way of Q2 to M1). Connect the B pin of Q3 through a small resistor to C pin of Q2.

Circuit at the beginning when the temperature is low will switch off the M1 by closing Q2. When Q2 is off, the Q3 is on and M2 runs. When circuit thermistor works, the Q2 is on, and fan motor m1 is on, Q3 is switched off and m2 stops.

That is the whole idea.

Of course, you had better to learn about the circuit techniques and then improve your own way.

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