What voltage for bipolar stepper 2 A, 1 Ohm ?

[vroemm]

Below is a bi-polar stepper motor is Iw=2 ampere, Rw=1 Ohm.
It is a:
ISERT zweiphasenschrittmotor 1.8 grad.
Art.-Nr.3455
ISERT ELECTRONIC.
Iw=2.0 A Rw=1.0 Ohm
WZ6 10479
A2405-9212-A2
Made in japan.

It has 8 wires, 4 coils.
Currently connected 2 coils in parallel, resulting in 2 coils.

I would like to use it with the L297/L298 drivers.
http://www.st.com/stonline/products/...re/ds/1334.pdf
http://www.st.com/stonline/products/...re/ds/1773.pdf

What 'Supply Voltage Vs' should be used for this stepper motor ?

Thanks.

[jeffs555]

From Ohms law, 2 amps at 1 ohm is equal to 2 volts. The general rule for steppers is to use a supply 10 to 20 times the motor rating, so something between 20 and 40 volts.

PS Since it is an eight wire motor, you can't really be sure what the rating on the nameplate is for. Generally, with an 8-wire motor, the rating is for a single coil, or unipolar connection. However, if it came wired for bipolar parallel, the rating may be for the parallel connection. If you have a meter with a low enough Ohm range, you could measure the coil resistance to be sure.

[t0mcat]

you seem to have the same stepper motor from ISEL. I cannot find data about it.

isertelectronic Zweiphasen Schrittmotor 1.8° Art Nr.3455
lw= 2.0A
Rw= 1.0 Ohm

Do you have some description about the cable colors?

[vroemm]

Originally Posted by t0mcat you seem to have the same stepper motor from ISEL. I cannot find data about it. isertelectronic Zweiphasen Schrittmotor 1.8° Art Nr.3455 lw= 2.0A Rw= 1.0 Ohm Do you have some description about the cable colors?

Below is a picture attached with the wiring.
It is as bipolar connected.

One Coil :
red/white and yellow
yellow/white and red

Other coil:
black/white and orange.
orange/white and black.

Which steppermotor driver are you going to use ?
I have been experimenting a little with the L298 + L297.
The driver gets very hot when the motor is standing still.
I have not yet found a solution for this.
Busy with other things :-)

[vroemm]

Originally Posted by jeffs555 From Ohms law, 2 amps at 1 ohm is equal to 2 volts. The general rule for steppers is to use a supply 10 to 20 times the motor rating, so something between 20 and 40 volts.

I still do not get this.
Its like a light bulb which has 11 volt printed on it, and the user must conclude that it can be used on 220 to 440 volt.
Not exactly exact info to go on.

Suppose:
Assume its a bipolar and current is for each 2 coils.
2 ampere tru wire, means 2 volt.
And P= U x I = 2 x 2 = 4 watt per coil. 8 watt for both coils.
You use 20 Volt power supply.
Then the steppermotor driver takes 20-2= 18 volt !
The driver then takes P= U x i = 18 x 2 = 36 WATT per coil.
Thats 72 watt in the whole steppermotor drivers.
And only 8 watt in the steppermotor.

This can't be right, is it ????????
I am very confused :-)

I am using the L298/L297 drivers.
And the driver gets rather hot.

[ger21]

The 10-20x rule is for a chopper drive, where the higher voltage allows more current to get to the motor at higher rpm's, giving you more speed. I don't think the motors actually see the higher voltage.

[t0mcat]

What a pitty. The colors seem to be different at my motor. Where did you get the information? Directly from isel?

[vroemm]

Originally Posted by t0mcat What a pitty. The colors seem to be different at my motor. Where did you get the information? Directly from isel?

It was connected like this when i got it from a scrapyard.

What are the colors of the wires on your steppermotor ?
You can at least measure which wires are connected to the same coil. There are 4 coils.
If you then put the color combinations here then we might (or might not) be able to help you.

[t0mcat]

I have two different motors. I post the wire colors of both of them.

The first shows the 3450.
This has the coils:
yellow <-> black
green <-> green-white
red <-> red-white
blue <-> blue-white

The second image shows the one with the number 3455.
This has the coils:
blue <-> black
orange <-> white
red <-> violet
yellow <-> brown

[vroemm]

Hi T0mcat

I can't figure out the colors.

I am not experienced in this.
But perhaps there is a other way to figure it out.

Write down all possible wiring combinations.
Writing it down is very important, because you might lose track of which combinations you tried and the results, if you do not write it down.

There are a lot (?), but still a limited number, it is do able.
Then try for every combination how much weight the steppermotor can lift, and write the result down.

A simple method to measure the weight it can lift might be this:
Put a weight scale on the floor.
Put a suitable object on the weight scale.
For me it was a +/-15 kilogram toolbox.
Fix a rope to the toolbox, and fix the other end to the steppermotor axis.
At first the weight scale will point to 15 kilogram.
The let the steppermotor slowly pull the toolbox up.
If the weight scale then points to, for example, 12 kilogram, then 15 -12 = 3 kilogram.
Then you know the steppermotor lifts with 3 kilogram.
Write it down.

If you find a combination which works well, then still try all other combinations.
Just to create certainty.

You will then find there are at least two combination which work well, but will make it run in opposite directions.
Which will be the same combination, except with the poles reversed connected.
This can act as a double check to see if you have the right combination.

Theoretical you should be able to find the right combination with this method.
I think, perhaps, i could be wrong :-)
I have often a idea, which later turns out does not work :-)
This might be one of them :-)

Anyone a idea what is wrong with this method ?

[lucas]

I used the method below several times, it works and is quite easy to do:

You need to find the 2 pairs of matching coils and their polarity.

You could try this:
Pick one of the coils and run a current through it from a battery or PSU through a resistor. Current depends on the motor, something like 0.5A should do it.
The motor will lock in a position.
Leave this coil connected and apply the same current (Important: same value of resistor)
to the 3 other coils in both directions (6 configurations).
Note down where you connected the + and - and watch what the motor does, you might need to mount a lever on the shaft to see it clearly.

On 2 of the coils (4 configurations) you should see the motor step the same amount CW or CCW when you apply the current and return where it was when the current is removed.
These are the 2 coils wich make up one winding, let's take the configuration where the motor steps CW on each winding: note where you put the + and - on the wires, now you have fully identified this winding.

The 3th coil should lock the motor stronger in position with current in one direction and unlock it with the current in the opposite direction.
This one and the first coil make the other winding, the correct polarity is of course the one where the motor locks up stronger, note the polarity of the wires and you're done.

[vroemm]

Lucas,

You method sounds easier.
I would try your method first.
I have bookmarked the message, i case i need it :-)

Thanks.