stepper driver misbehaviour
stepper driver misbehaviour
(OP)
hi guys, recently ive been dealing with l298 stepper driver and using a l297 to control it through a 8 bits MCU in order to develop a small movement control system. the motor consumption is 1,2 A. power supply is 12vdc
i found two problems when testing:
1. when inserted an amperimeter (multimeter) to check the current, the stepper motor delivered more torque than if i dont use the mmeter to make the measurement.
i supposed that was because bad filtering at the supply. then i filtered using a choke and capacitors. i got the same result. unfortunately at this moment i dont have a scope to view the signal. i think it is not the supply. maybe the amperimeter is generating spikes but im not sure.
2. the l298 rises the current consumption but its temperature is just warm; it rises about 0,1 A per second. i always turn off circuit when near to 2 A sems to be a unnatural runaway. the L298 is not defective, nor the motor.
any tips?
regard
killa
i found two problems when testing:
1. when inserted an amperimeter (multimeter) to check the current, the stepper motor delivered more torque than if i dont use the mmeter to make the measurement.
i supposed that was because bad filtering at the supply. then i filtered using a choke and capacitors. i got the same result. unfortunately at this moment i dont have a scope to view the signal. i think it is not the supply. maybe the amperimeter is generating spikes but im not sure.
2. the l298 rises the current consumption but its temperature is just warm; it rises about 0,1 A per second. i always turn off circuit when near to 2 A sems to be a unnatural runaway. the L298 is not defective, nor the motor.
any tips?
regard
killa





RE: stepper driver misbehaviour
RE: stepper driver misbehaviour
regards
killa
RE: stepper driver misbehaviour
RE: stepper driver misbehaviour
when i dont use the amperimeter and try to stop motor it losses steps.
the thing is that i can see that im not getting plenty of power from the l298. im trying to get the best power allowable.
anyway ill keep checking with a well filtered supply.
regards.
killa
RE: stepper driver misbehaviour
RE: stepper driver misbehaviour
RE: stepper driver misbehaviour
cbarn: at 1A it is good torque but it depends on the mode used to drve the motor, the 2 phase mode gives the highest torque but other modes provides weak power and the shaft is easily stopped with fingers.
now im creating the ramp to accelerate and decelerate the motor, but i can see 2 possibilities:
1. controlling the frequency in the clock
2.controlling the vref in l297 which controls the current delivered to the wires.
with pwm from my mcu i can easily create a dc ramp to accelerate the motor. but not sure if it is correct.orif should be in the clock.
regards
killabyte