First step motor.

[Lou123]

Hi,
To learn how to use them I purchased a used step motor on eBay and I am planning to do some learning testing with it.
First the step motor is a POWERMAX II 1.8 Step Motor Model P2HNRXC-LNN-NS-00. I went to their site to get some info, but I was unable to find which voltage to use.
Some of my immediate needs are:

• Which voltage and transformer is needed?
• How can I test if it is working, if I just have the step motor?
• If I want to go further, where can I find a controller easy to build to be able to do some testing from my laptop? Obviously the controller should be adequate for this specific step motor.

I must say that it would be the first time I play with a step motor and I could ask some really stupid questions.
Thanks for any help.

 

[Ubergeek63]

https://www.electro-tech-online.com/custompdfs/2010/04/powermaxII.pdf

unipolar 5V 2A per phase

 

[shortbus=]

Steppers are very unusual motors, yours can be operated three different ways, unipolar, bipolar, and bipolar parallel. It all depends on what your trying to do with it.

The voltage on most steppers is not run at the rated(specified) volts but at 10 or more times the rated voltage. The higher voltage makes each individual "step" snappier or faster. Not the RPM, just each step.

The main thing to worry about is the amperage rating.

If you go here; Jones on Stepping Motors This is the "manual" on all things stepper, although it is getting out dated by the newer drivers.

 

[kinarfi]

So as I read the 3 posts and follow the links, I come to the conclusion that the control of a stepper is done by control chips or such and not something for the hobbyist per se. Is that correct or can a stepper be controlled similar to a DC motor being controlled by an H bridge and PWM?
That is, I can design and build a controller for the DC motor with some FETs and some Quad op-amps and components, Can a stepper control be designed and built similarly?
Thanks
Kinarfi

 

[shortbus=]

A stepper is definitely hobbyist friendly, but not driven by PWM and a H-bridge. The various stepper drivers make it easier to drive and are a lot cheaper overall to implement.

A unipolar is the easiest to drive, but also gives the lowest torque output.

The individual coils of the motor are switched on and of in a predetermined sequence to make the motor move, that sequence has to be obeyed to get the movement. The speed of movement (RPM) is controlled by the rate at which the sequence is repeated, not the voltage, not like a DC(brush) motor.

The driver allows the motor to be moved, just one step at a time, a predetermined number of steps, at a certain speed, or stopped and holding position, just by giving it the correct commands. That can be done by, switches, a CPU, or a PIC, depending on your needs.

 

[kinarfi]

I started to ask a long hard to explain question,but instead what's a PIC # I can look up and start investigating?

Thanks

 

[shortbus=]

A micro controller

 

[kinarfi]

A micro controller

Thank you, but that is not quite what I meant, rephrased, what is the number of a PIC so I can look it up and see what I'm going to have to learn to use a stepper. Are they capable of much torque?
Thanks
Kinarfi

 

[shortbus=]

I'll probably get heat for this, but I wouldn't use a PIC to drive a stepper motor. If you search the archives you'll find a lot of threads asking about "whats wrong with my stepper code"

What I meant by using a PIC, was using it to give the signals to a stepper driver IC (speed and direction). The sequence is built in to a driver IC. Then all you need from the PIC is speed(a square wave) and direction ( usually a high or low depending on the driver). No sequence code needed.

Unless you just want to learn how to write that code.

As far as torque goes, there are all different torque ratings available. From a few ounce/inch to tens of pound/feet. Depends on what your doing.

 

[kinarfi]

I would be wanting tens of foot pounds and a controller that is voltage sensitive, that is, on 10 volt system, 4.5 to 5.5 volt no movement, above or below that, one direction or the other (numbers are arbitrary, it's the idea I'm trying present).
Don't want to be doing a lot of programming and it would be for a power steering assist project, currently using a DC motor.
Thanks
Kinarfi

 

[shortbus=]

That sounds like the system that I'm using on the EDM(Electrical Discharge Machine) that I'm building. It uses a window comparator to measure the voltage in a spark gap to control the gap. Voltage high it feeds down, voltage low or shorted it feeds up, voltage in the window its stopped. It uses a stepper motor to move the electrode in the gap.

Here is a link that will show some different motor ratings; Stepper Products While they have pretty good prices for new motors, if your just wanting to go with a used one, E-bay is a good source.
cary

 

[TechnoGilles]

One thing you need to know about steppers is that they "permanently" rotate by themselves. Instead, each individual phase of the stepper, when powered, will move the motor's rotor in one position and hold it there. If you remove power from the first phase and power the next one, the rotor will turn a few degrees (depending on the stepper characteristics) and stop there. If you power the first and second phase simultaneously, the rotor will stop in the middle.

Continuous rotation is obtained by turning the phases on and off at the proper time, in the proper sequence. Stepper drriver ICs are design to implement such a sequence and simplify your life !!