How to stop a motor in this project?

[unleashed]

hi there
here is the link of my project

https://www.redcircuits.com/Page109.htm



i have a project..and i have to ask something about how to stop the motor

let consider we have a motor (dc) .producing temperature..and a thermistor (ntc) is there...if the temperature is increased another motor(fan) is running to cool the system...
my aim is how to stop the running(dc motor ..first one..that produces temperature)
automatically means that fan is in working conditon and the same time the first motor stops..
please help me to complete this project

 

[master_picengineer]

HOW TO STOP A MOTOR

Switch off Q1. This depend on R1 so temperature.

 

[Borber]

Re: HOW TO STOP A MOTOR

Well here are two possible cases.
One is when you want to switch off motor completely when it reaches certain temperature and external reset is needed to switch it on again.
Second case is when you want to switch of motor for the time it cools down to certain temperature and after that it is switched on automatically.
In both cases temperature can be sensed by monitoring M1 voltage because it is directly proportional to temperature of thermistor.
You need a comparator, RS flipflop and motor switch for the first case.
For the second case you need comparator with suitable hysteresis and motor switch.

Comparator can be LM311, RS can be realized with CD4011 and motor switch with BD139 or BD140 respectively.

Sunny side of Alps

 

[Aum]

Re: HOW TO STOP A MOTOR

put one push to open button across Q1 and try it!!!!!!!