hall sensors instead of pots !!!

The back of the mosfets (cooling fins with the screw hole) are electrically connected to their drain. You have to be very careful how you connect them not to short anything out. Don't connect them to any ground!

hey frakk,

i can't follow you completely, ok the back of the mosfet (alu/metal) piece you can't connect to ground i now but, ru.null is talking about wire from the back of mosfet to motor somewhere i don't know.

Or are you talking about this in particular ? or you mean just don't connect back mosfet to ground
?

The motor connectors are not connected to ground,they are connect to the drains of both upper and lower mosfets on each side. Therefore you can also connect the motors directly to the cooling tabs because it is the same electrical point. Just be very careful not to short anything unless you like the smell of burning epoxy and melting wires on the board.

ok i follow you i think, (never learned for electronics just a bit of a hobby). But if i'm correct i connect one wire to housing of motor in other words the minus or the rotor wire.
Can you put it in scema for me because i don't want burning at all.

my motor frames are not isolated

I don't know how you have the motor wired up.

Basically: connect one motor wire to the tab of one IRLZ44N, connect the other motor wire to the other IRLZ44N tab. If you want it to revers just switch them up.

this is how it is connected

Hi Pim!

I connect motors directly to cooler mosfets. Blue and yellow wires on the fotos. How Adam said, this is the same as the drain.




I did not know why you got a problem with connecting ground. This is my second Hbridge with this modification and have no problems. Also I am a little rebuilded PCB and etched this ways.

pim, be very careful mounting the motors. Do not forget, when the motor is spinning in one direction, your case will be ground, but when it is spinning in the other rotation, the case will be 12V PWM. If you have the motor connected to the frame or any other parts without electrical isolation, you run the risk of shorting it to other parts.

hi guys i would like to understand more the mechanical setup of the hall effect sensors . i know pctures have been posted but i am still missing something about the type and shape of magnets which give the best results, i have some old hardsicks which i can pull apart to get the magent , is there a better source or site where i can order the correct magnets for this setup .. sorry if it has been explained before but would appreciate any help in the form of a sketch showing the location of the hall effect sensor and shaped magnet Please

hi guys back again --- found some info in another post so will try to get some bits form my experiment thanks would still like some sort of sketch if possiible ,as i understand mechanics better than electronics and so useually try to think of the mechanical equivelelnt to better understand where possible electronics Cheers guys

Have a look at this forum. for a good explanation.
http://www.mycockpit.org/forums/content ... a-joystick
Douwe

Hi Douwe many thanks for the tip i have just read the info and it is exactly waht i was hoping to get in the way of information, like i said i tend to where possible try to understand electronics by thinking about the mechanical equivelent works sometimes other time :-( but this article is a great link am about to destroy and old unused Harddrive to get the magnet but looking at the way that article explains the method of operation i may just try an experiment with one of my standard magnets . hows your project going .i have not been to your site in a while , will have to check out your latest development if any available Thanks again Douwe

Due to post processing moving house, vacation and real glider flying,
the progress is very slow on the moment.
Douwe