JS1
I'm a newbie when it comes to electronics, so perhaps (definitely) a stupid question here .. I have installed the 2.5 motor controller/H-bridge with speed control. Added the PWM controller in the project and can modify PWM between 0 and 100.
Now the question .. when setting PWM to 100, will the + and - going to the DC motor be exactly the same as when connecting the motor directly to the 7.2V battery ?
The reason I ask is that when I connect the motor to the battery directly, it runs, when when I connect it to the motor controller with PWM=100 it doesn't run (I set also the forward/reserve digital signal). I have an amp meter from my father (which I don't understand really how it works ), but I see the needle swinging to the right when connecting it to the motor controller (exactly the same as connecting it to the battery). Setting PWM=50, the needle swings half way as I would expect.
Thanks and regards Johan
The white button gives the motor controller the ability to either take 5 volts from an outside source, or make its own 5v source. Pressed in, it's making its own. Out, it is waiting for 5v on the 5v screw jack. So that's why when it's out, it doesn't work.
The 5v is for the main control chip, as it only is able to use 5v. The battery power is moderated by this chip, and it sends the power required for what setting you set, by pwm.
What logic are you applying to In1 and In2? Depending on the logic will depend on the voltage across Out 1 and Out 2.
If In1 is high and In2 is low with PWM of 100 on EnA Out 1 to Out 2 should be the same as VIn. If both In1 and In2 are low with any PWM Out 1 to Out 2 will be 0.
This is my current script to move forward
servo(D4, 37) #servo used to either go forward, left or right
PWM(D19,99) sleep(100) PWM(D19,100) set(D15,off) #reverse off set(D16,on) #forward on
When I run the script, I get voltage on Out1/Out2 as I would expect.
I'm still struggling with this. I did some more test and the following seems to happen :
When running the above script, the H-bridge brings a voltage to the +/- of the motor (I can measure with with my analog device). Then, I connect one end of the motor to out 1 .. no change. Then, I connect the second wire of the motor to Out2. The moment I do that, the voltage output from the H-bridge drops to zero.
The motor runs when I connect it directly to the 7.2V battery
What am I doing wrong ?
thanks and regards Johan
Sounds like maybe the motor is drawing too many amps and browning out the controller. The 2.5 amp controller is for fairly small hobby motors. If you are trying to drive something like a windshield wiper or wheelchair motor it is totally inadequate for the task.
Alan
From your labeled pictures, you show the ground going to D19 ground. I assume since you are having partial success that the battery ground is going to the EZ-B? You must have shared ground even if you have separate power for this to work.
Alan
hi Alan
i only have one battery. Ground goes to EZB and D19 ground to H-bridge.
I'm using a small 7.2V DC motor from a Tamiya 1/16 scale Remote control tank. But I do not have a spec of it, so I don't know the amp is will draw.
Thanks for your help Johan