I have the spindle drive motor out of a Toshiba CD-ROM drive that has a rotor that's a steel cup with a magnetized ring inside, I would guess it has multiple poles. This fits over a laminated stator of 9 arms, each arm having a coil of wire. There are three pads for the wires from the stator. I'm not sure how the stator is wired, maybe three sets of three arms in series? There are also three Hall effect sensors(?) there, too.
I have a red LED soldered across two of the pads, and when I give the rotor a real good spin, the LED lights up brightly. I can measure the DC resistance of about 3 ohms between each pad and they're all equal so I would say that this indicates the windings are equal, i.e. they are not center tapped. What I'd like to do is rectify the AC output of the three pads, but how? Should I use 6 diodes like the alternator in a car has? Or treat it as a center tapped winding?
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
These alone make disassembly of old floppies worthwhile, too.
This is a good strategy. Of course, the low output voltage might be problematic for some, but you have a god deal of experience with electronics so you can probably visualize at least three ways to do this effectively. Pick two points and call them minus and plus. Pick a third and call it common. From each winding, take one wire and run it to the common point. Take the other and put a pair of diodes on it- cathode from one, anode from the other. The other ends of the diodes go to the two plus or minus points like this: flying anodes go to the minus wire, flying cathodes go to the plus wire. Any capacitor would then go from plus to minus for full voltage, or you have the option of using half voltages from the coil common to either the plus or the minus. This gives you bipolar supply capability, or you can just ignore it. Of course, if you don't mind the excess drop, you can use a bridge rectifier on each lead and common all the plus outputs and also common all the minus outputs, but this is really wasteful. And, use some Schottky rectifiers for the best output overall. They are pretty common on old modem cards and other computer cards as surface mount devices.
In article , snipped-for-privacy@OVEcfl.THISrr.com mentioned...
have
the
rectifier
the
Perhaps I didn't make it clear enough. There are only three pads for all the windings. I think this means they're connected as a wye or "Y", not Delta, because I see only three wires coming from the coils down to the pads. From your description above, it seems that you're describing how to connect three separate windings, i.e. six leads. If I connect any winding wire to another, I'd get a short. At the bottom of this web page there is a schematic of an alternator stator and rectifier bridge. I believe that's the way the windings are connected on this spindle motor, and I'm guessing that's the way I should connect the six diodes, as shown in this schematic.
formatting link
I bought a bunch of 1N5818 schottky rectifiers, so no problem there. I haven't had much success in IDing the surface mount diodes or transistors from PC boards. Some of the three terminal devices on PCBs are marked diodes, even tho they're in a transistor package. That's enough to mess with your mind. I'm still trying to ID some smt transistors, but the lists I've found don't show them. And this is even tho the PCBs are from the mid-'90s -- five or ten years old. Thanks.
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
Google Groups can't resolve the proper address, so I'll post here in the thread.
Yes, you are correct and that excellent drawing shows it well (a lot of photos & graphics for a dial-up connection). The in-phase winding outputs upward thru its diode in the upper group and the return current from the out-of-phase windings goes down thru their diodes in the lower group.
I still think the Delco print contains all the ideas you need. Center-tapped is not necessary, in fact the voltage in that 3rd winding will buck what you get from the other 2. You will also lose the 3-phase advantage and get a lumpier DC. ....... | . | . | . | . | Va-b = 1.732 * Va
In article , jeffm snipped-for-privacy@email.com mentioned...
> You will also lose the 3-phase advantage and get a lumpier DC.
Yeah, I would think that the center tapped wouldn't be a good as the full wave. But the full wave has an additional diode drop per leg. At these low voltages, that might be more important. Thanks.
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
Have you considered making the bridge out of six LEDs, and putting a resistor between the + and _ outputs to set the current? You should get more light, and waste less cranking energy getting light.
Well, right now I'm still using just a single LED, no resistor, nothing else. Can't get much more efficient than that. But I thought that it might be a good idea to use the rectifiers if I put a big cap on the output to store up a bit of muscle power. I was thinking maybe a couple 1F caps might help... ;-)
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.