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I don't care about the torque/max velocity.I don't care about maximizing strength/efficiency. I'm a beginner and I'm almost at the point were I can get a motor to move. I just want that for now, so I can fiddle with it and learn.Question: so how can I set up a " current monitoring and adhusting system"?I can use transistors, yes? (I don't know enough about circuits yet. Still reading)Tell me if the following is true: I just need to increase the current somewhere between the driver and the motor, right?Then the thing will turn w/o anything burning up? (again, neglect efficiency).
Actually I don't think I can do that first suggestion.[...]My motor: http://www.automationdirect.com/adc/Shopping/Catalog/Motion_Control/Stepper_Systems/Motors_-z-_Cables/STP-MTR-23055[...]So yeah, the bottom line is I screwed myself because I didn't have enough understanding before I started ordering stuff in the first place, and now I have to make it work with this stuff or I can't justify ordering more because its not my money.
Hi,You sure did, but hey, call it a learning experience and it ain't all bad The driver I posted wouldn't work anyway, as you bought yourself a step motor.I assume you got the 2.1V from the 2.8A and 0.75 Ohm spec(?) but a stepper is sually driven from a higher voltage with a chopper or similar to back off the current when the field winding is near saturation - that's why it hasn't got a voltage spec.You can still make it move though and with a resistor in each winding (two in total, as it's a bipolar motor) you can keep the 754410 (1A out) alive.Carbon/zinc cells are the lowest quality of all battery technologies and won't work for long, but aiming for the 6V Lantern battery, a 3.3 Ohm (4W or higher) resistor will keep your driver alive, as the driver itself will "steal" around 2V of the available 6V. The motor will probably not be able to run/drive anything that way, but it will let youexperiment with making it go.Did you buy a stepper on purpose, or did you mistake it for a regular DC motor?If so, you might be able to trade it in for a suitable DC motor, but the one you have ain't half bad, provided you build or buy a proper driver for it.
Besides experimenting, do you have a future goal/purpose for this motor?
So essentially I just need to add two resistors to appropriate places in the circuit to prevent anything from smoking?
Would it be OK for me to draw up a circuit diagram and ask you or someone else here to double-check it for me?
So overall, the idea here is to protect the driver by diverting some of the voltage to resistors?
The driver you posted involved several transistors, right? Is there a way I can use transistors in the circuit to increase the current going to the motors?
I purposely bought 3 of that stepper model because I originally intended to make robot limbs (arms and legs) and eventually a completely humanoid-shaped bot (though not life-sized). I had to keep scaling back as and putting goals off as I learned more about what skills were needed. Originally though I just bought some stuff to jump in and get my hands dirty, and learn as I go. Things haven't been going as smoothly as I hoped, but I don't care, I sill love doing this kind of stuff.
Yes. It's gotta be power resistors though.
If you still have the connector on the motor, one resistor go to either pin 1 or pin2 (doesn't matter which) and the other goes to either pin 3 or pin 4.
OK, have fun with it (it IS), but consider getting those dirty hands on a DC-motor as well, as they are the bread and butter of motion control and is an easy first step to learn.You can either rip one from a toy car (or similar toy) a broken down VHS recorder, cordless drills/screwdrivers and so on - the size doesn't matter for experimenting
Here's the schematic.
Also, I mistakenly put 3ohm in the picture where it should have been 3.3ohm resistor.
Like this ?: http://www.radioshack.com/product/index.jsp?productId=12554561&filterName=Type&filterValue=5-watt+resistors
Why the hell are these things so hard to find? Radioshack sucks. I'll probably have to order those two little resistors.
Can I instead put 3 10ohm resistors in parallel to get 3.3 ohms? They are more likely to have 10 ohm resistors in store.
What is the "connector" you refer to? Is it one arm of the resistor?
Could run it with the other driver I have on hand (L193D)? Would experienced people normally use a driver like that for running a DC motor? Or a simpler driver instead?
Could anyone tell me if the schematic posted above would work?
Also, if I used a higher voltage battery, would I need higher ohm/ watt reistors? Or would the answer be no because the situation is that the motor is pulling current through the circuit as opposed to the battery pushing current through the circuit?
-Where do the 4 wires labeled "phase" lead to?
They come from the controller.
-The schematic specifies 24V supply at the top. Does that mean I MUST use 24V battery for this project? Or "12V" battery? Or am I still using 6V like I was originally going to?
-Why are we talking about 10 ohm resistors now when we use to be talking about 3.3 ohm resistors? Is it because we went from a 6V battery to a 12V battery? Or was that post just a very thorough example for a different voltage from what I'll be using?0 (if so, thank you so much again for going through the basics for me like that. You can probably guess how enlightening it is for me)
-When you said before that "If you still have the connector on the motor, one resistor go to either pin 1 or pin2", the pins you refer to are the 4 motor connector pins right?
-Are the black triangles on the right side of the picture diodes? Shouldn't they be white triangles, or am I mistaken?
-So besides the obvious (microcontroller, driver, battery, motor, breadboard and hookup wires), according to the schematic I also need 8 diodes, a 10 kilo-ohm resistor, and 2 3.3 ohm resistors? Am I missing anything?
-Do I really need those diodes? Would it be a big mistake to leave them out considering that the motor is not running full capacity/strength? I ask because dealing with the diodes is an element of uncertainty for me and I would rather avoid them this time if I could.-If I do need the diodes, do I connect them in series? Is that how the schematic is read?-What kind of diode should I get? Will any do? How about this one :http://m.radioshack.com/radioshack/product/detail.do?itemId=13015070&categoryId=&path=