I use velleman K8004 PWM controller card to drive DC motor. I have a problem that when I choose low frequency (by rotating resistor) the motor vibrates, when I set high frequency (5000Hz) I hear high pitch whine noise.
You'll have to experiment unitl you find a cap that doesnt affect your hearing.....or else change the value of the 2k2 resistor by half...The effect of that would be to reduce the charging time for the cap so the RC time constant is shorter and the frequency should go up...
The manual lists: 8-35VDC unregulated and figure A shows a simple diode bridge with capacitor as power source. But since I use configuration C that shows internal reference voltage used as control coltage. This means if my DC current is unstabilized by LM338 the motor speed will change as voltage changes right?
I will use slowest motor rotation mode possible so that means that LM338 is a must no?
If you use figure C, just connect a potentiometer value 1k as per the drawing, using Vref,
connect your dc power supply as shown, the motor speed is then controlled by the new 1k pot....
sory that i bomb in here, i just have a question conserning the power of the k8004, i have a DC motor (24VDc 14A) fedet vit 24DC care bat.
I like to controle the motor with the kit it just sems that it are loosing power.... schoud i ad on a nother fet, an hau?????
it works fine until i ame puting some balast on it then it daies out.... and it can not be the curent ther ise plenti..... I have a der that it might bee the Diod acrose the fet.???
It seems I need to use bypass cap for the motor, what value would be better?
I read to use ceramic, but why not polyester they are cheaper, would 0.47uf work?
Furthermore I read about adding a diode, but my controller has one at the controller side.