has any one had luck with 0.6a steppers?

[opusinwood]

I have bought and assembled 3 x chopper driver boards with half step function and 3 x 222oz/in 0.6a motors, and a ppt breakout board

have not hooked it up to any machine yet.

using mach 2 demo mode it seems to go ok but anly about 2 or 3 revs per second and then ffftt bzzzz...

i have spent $100 aus each on these motors

ideas anyone??? please

[homebrewCNC]

what type of power supply are you using?

[BCwanderer]

Your motors appear to have high-resistance because of high winding count and small wire size.
They probably need a higher voltage to run them.
I suggest you increase the voltage on your drivers within their spec limits.
If the internal coils are wired in series, you can open the case and wire the coils in parallel - bipolar. That would reduce the voltage requirements.
That would also increase the required current and reduce the impedence.
Be careful not to remove the central core. Sometimes removing the core will alter the characteristics of the motor.
Some of the older high impedence motors quickly resonate, limiting the maximum speed they will run.
If you are going to replace them, look for motors with low resistance.

[ger21]

Sounds like they are 12V or 24V motors. Ideally you'd want 2-3V motors, no more than 5-6V max for any kind of decent performance.

[jeffs555]

Low current high torque motors generally have much lower top speeds. Torque is proportional to current times the number of turns of wire in the coils. To get higher torque with low current requires more turns in the coils. More turns means more inductance, and inductance is what limits the speed of a motor.

All the things that BC said will help, but if your speeds are that low with no load you may never be happy with the speed. Speed is proportional to supply voltage so doubling your supply voltage will about double the speed. Need to know what type drives and how many wires on your motors. If they are unipolar drives, there is not much you can do other than increase the supply voltage. If they are bipolar drives and 8 wire motors, make sure the motor is wired parallel. If 4 or 6 wire motors, you may be able to modify the internal coil connections like BC said. I have done this with some 6 wire motors with good success.

[opusinwood]

the power supply is 24v 150w
the controllers are L297 - 298 capable of 36v
I have not come across a 36v supply and wouldn't know how to modify the exsisting situation.
the motors are bipolar 4 wire

thanks for the interest

[ger21]

What are the motors rated voltage?

[jeffs555]

Like Gerry said, you need to look at the rated voltage of the motors. I would imagine that yours are somewhere between 12 to 24 volts. The power supply should be at least 8 times the motor voltage, so for reasonable speed you want motors less than 4 volts. If your motors specify a resistance and not a voltage, just multiply the resistance times the current to get the voltage rating.

Many 4 wire motors actually have 4 coils with 8 wires internally. It might be possible to carefully open the motors and change the internal connection from series to parallel. Doing this would give you about 4 times your current speed and require twice the current.

Your best bet is to just get different motors. Going from 24 volt supply to 36 volt supply will only increase speed 1.5 times, so won't help much.

[opusinwood]

alright

model 23hd803; 4 wire; hold Tq 16kg.cm; 0.6A; phase r 12mh; inductance 20; detent Tq 0.7;inertia 700

I have bought a Sanya Denki 103H716-0440 1.27Nm hold Tq; 2A; phase r 2ohm; inductance 4.5mh
this is a unipolar 6 wire, however 2 out of three advice suggested use the coils without the tapped centre wire and hey it works.

I've connected it to a MDF Jgro with 900m X axis althread and it works at about 18" per minute travel and i can't hold it back by hand, so Im happy.

but theres still three motors 12ohm , 0.6 amp 20mh induct.

so if I reconnected it from 4 coil series to paralell would that be;
3ohm 2.4amp and 5mh inductance.

and if so how is it done?

is it uncoiling the winding, rearranging and rewinding
or
working out the inwires and outwires, snipping, pull across and connect to the apropriate connection.

As you can see ive not done it before. And I'd like not to make a mess of it.