DC Motor Control Circuit Problems

Thread Starter

Dinel

Joined Mar 2, 2016
9
I've created a simple H-Bridge circuit to control a 5V DC motor, and I'm trying to have the motor go forward when a normally open push button is pressed, then have it switch to reverse once the output of a photoelectric sensor becomes true (which will not be held). I'm not sure how to latch the motor into forward, then unlatch the forward and latch the reverse. Any input would be appreciated. I attached a picture of the way I'm seeing this circuit in my head (in ladder logic), and once again, I'm just not sure how to create this with a small budge and a 9V - 5V power supply. I have the supply switching, emergency stop, and everything else figured out, I'm only trying to figure out how to switch inputs without having to hold a button or anything.
 

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ronv

Joined Nov 12, 2008
3,770
I've created a simple H-Bridge circuit to control a 5V DC motor, and I'm trying to have the motor go forward when a normally open push button is pressed, then have it switch to reverse once the output of a photoelectric sensor becomes true (which will not be held). I'm not sure how to latch the motor into forward, then unlatch the forward and latch the reverse. Any input would be appreciated. I attached a picture of the way I'm seeing this circuit in my head (in ladder logic), and once again, I'm just not sure how to create this with a small budge and a 9V - 5V power supply. I have the supply switching, emergency stop, and everything else figured out, I'm only trying to figure out how to switch inputs without having to hold a button or anything.
What does your H-bridge circuit look like?
You could use a flip/flop http://www.intersil.com/content/dam/Intersil/documents/cd40/cd4013bms.pdf , or a set/reset latch: http://www.mouser.com/ds/2/405/cd4043b-404165.pdf
You may need something to turn it off or it will go forward or backward forever.
 

TheButtonThief

Joined Feb 26, 2011
237
First of all. Are you programming a PLC, a micro, building a circuit...? If you're representing the logic of your control using a ladder diagram, it suggests that your project is electrical bias moreover than electronic. Does this mean that you're looing for an electrical solution (PLC program, relay wiring diagram...)? Or are you looking for an electronic solution (logic IC's, micro controller, discrete components...)?

The solution you're looking for is simple but I'd need to know what format to present it in.
 

Alec_t

Joined Sep 17, 2013
14,280
Your motor (depending on its spec and attached load) may not like being reversed instantly. Are you intending to allow some delay so that it can come to a stop before being drive in reverse?
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
Yeah, it is handy, the only think now is that wiring overloads (O/L) on the neutral or RH side of the coil is considered bad practice, they should now be in with the other logic LH string.
Mostly only relevant for AC circuitry.
Max.
 

Thread Starter

Dinel

Joined Mar 2, 2016
9
Your motor (depending on its spec and attached load) may not like being reversed instantly. Are you intending to allow some delay so that it can come to a stop before being drive in reverse?
Optimally, I would like to have a delay, but as I am running out of time with this project, I just want to make it latch into forward, then unlatch forward and go to reverse, then unlatch reverse and stop.
 
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