Over Rating a Stepper, any consecuence?

[roberto]

I have been looking thru forums but no real answer found.

The situation its simple, I build a Home made board (thx to a friend David Setya Atmaja) to control 3 unipolar steppers (Vexta 5-Phase) rated at 12V 2.0 amp.
Recently i lost the 3 motors (some acid burn them out ) i was trying to find another 5-phase set of steppers but with no luck, so i decide to use a reprogrammed firmware to 2-phase steppers, but once again NO LUCK with the specs so right now i got:

12V 2Amp Controller Board
6V 0.7 Amp Vexta Steppers

The question is, will my motors die with that current?
It is 12V 2AMP too much for them?

I got in mind, 3 coils x 0.7amp = 2.1Amp (no problem right)

But what about that extra 6V? How that affect?



Thanks in advance,

Roberto R.

[jerber]

If your board has some kind of chopper circuit, wich limits the current, it should be ok.
If it doesn't then you need voltage dropping resistors.

6V / 0.7A = 8,57 ohm ==> 10 ohm 5 watt resistor.

btw those 5-phase steppers are rare.

[roberto]

Originally Posted by jerber If your board has some kind of chopper circuit, wich limits the current, it should be ok. If it doesn't then you need voltage dropping resistors. 6V / 0.7A = 8,57 ohm ==> 10 ohm 5 watt resistor. btw those 5-phase steppers are rare.

Well thx for the reply, this may sound a little dumb but....i dont know if there is a chopper circuit on that design the term is unknown to me

Yes, the 5-Phase steppers are very rare (even in my country :P here u can find almost anything rare) thats why i switch to 2-phase steppers, they were more accesible and easy to find.

There is the schematic on the attached files if anyone want to check it out and give some light.
Thx for the help

[H500]

The circuit is not a chopper. You need to add power resistors to limit the current .7 amps per coil, or your motors will overheat.

[hunter07]

and this circuit has not real 5 phase driving system
[IMGW]http://www.orientalmotor.com/MotionControl101/images/101/5-ph-fullstep.jpg[/IMGW]

[hunter07]

and this circuit has not real 5 phase driving system
[IMGW]http://www.orientalmotor.com/MotionControl101/images/101/5-ph-fullstep.jpg[/IMGW]