JackH

Well, This may help but I am new to electronics and am not familar with any of the items you mentioned. I might add, This motor run's at over 5,000 rpm, the coils need to be powered two times per revolution of the motor, so they will need to be powered on/off at over 10,000 time per minute. To make a little more clear. I need someone to look up the H21A1 opto sencer from www.fairchildsemi.com and find out the voltages it needs at the anode to light up the diode. Also need to know how much voltage the mosfet needs at the gate to open it up. And how to setup the circut to get these voltages when using 36 vdc at the input. Any and all help would be appreciated. Later,,,,Jack

hotwaterwizard, The coils are fired with the opto sencer. A small disk is mounted on the motor shaft with two slots cut in it. This disk turns the opto sencer on/off. For every revolution the motor turns the coils should fire twice. I kinda thought the mosfet would work better because of the reverse emf diode it contains. This diode returns some power back to the battery when the coils colaps. However I am not picky, If you have a better idea for the control circut I would really like to see it. Thanks,,,,Jack

Hello All, I have a question, and would be very gratefull if some one could help. I am currently working on a new type of DC electric motor, the current version of this motor uses a set of motor cycle points to turn the coils on/off, causing alot of drag and arcing across the points. Was wondering if the MOSFET circut that I have drawn up will work instead of the points. And if so could some one tell me what the R1 and R2 resistence should be. Or if the circut needs totally changed.