please help nema 34 motors no power

[garydunlop]

i have 2, nema double stack 34 stepper motors at 6.5 amps each and 2, driver boards RM B4DB 20v to 50v up to 4.5amp output. now there only driving 1.8mts screws on a plasma table, problem is i used to have a 24v 6.5amps transformer powering the 2 motors and if i grabbed hold of the screw lightly it would stop the motor,, so got a new tranformer today thinking this would be the job,, it is 38 volts 11amps output. so wired it up but still no difference i thought it should be a little better at least, maybe there is something i am missing here ,that needs adjusted, all help would be very appreciated?????

[James Newton]

Sounds like a driver problem. A quick search for RM B4DB didn't turn up anything. What driver is that? Are you sure you have it set for max power output?

[garydunlop]

hey james i got the motors and drivers from www.rhonmac.co.uk there RM 4DB driver board has a selection of dip switches on the side i have them set at full amps output and have tried all different pulses/rev settings but no good also tried changing the amp settings incase the on indicator was on the wrong side, its bit down hearting to buy stuff and find its not right, but its a great learning curve!!! is it correct the volts input to the motor is the motor speed,, and the amps input to the motor is the motors power maybe i need 50 volts input but then again the motors had no extra power with the transformer changed??

[garydunlop]

Oh another question which would be better or have more power ,parallel or series on the 2 phase 4 wire nema motors??

[James Newton]

All the connection options (and the pro's and con's) are listed on this web page: techref.massmind.org/techref/io/stepper/connections.htm

The rhonmac.co.uk web page doesn't seem to what to load for me... not right now anyway...

That certainly sounds like a bad driver... have you contacted their technical support?