Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: dgalaxy on August 02, 2007, 10:52:45 AM
-
Hi im getting my cnc hobby stuff dialed in and i have a question i have my nema 23 motors tuned at 400 and 12 pulse 5 and 5 i was running mach 2.40 at 25k pulse for awhile then i up graded to a newer version and i got a message saying that my motors where tuned to fast for pulse frequency the motors didnt really seem jerky as a matter of fact tey seemeed to run fine but im not trying to break any speed records either... but on a single note if i try to run a program with alot of arcs it seems to over cut and under the stock kinda like missing steps and cutting to far one way or another but i cant see the motors acting funny. But like on regular squares and stuff circles its fine.
I geuss what im asking as a GREEN HORN how does pulse frequency effect tuning ?
Also if it is set to low could you miss steps and screw up your job?
John
-
Pulse frequency sets the max pulses that Mach will put out to your motors. If you have it set at 25KHz then you can have a Max of 25,000 pulses per second for each axis. If for example in motor tuning you have a step per unit of 2500 that will mean the max motor speed will be 25,000/2500 = 10 Revs per second = 600RPM
Hood
-
OK big Help thank you for clearing that up for me A WHOLE BUNCH
John
-
Try it this way -
If your stepper motors require 200 pulses per revolution and your have the driver card set to 8 pulses per step, then Mach3 must put out 1,600 pulses per revolution of the motor. If you have say a five to one step down on your stepper motor to axis drive, then Mach3 has to put out 8,000 pulses to drive the axis screw round once, and if your screw moves the axis 1/10 inch per rev, then your need to put out 80,000 pulses to move your axis one inch.
In the stepper motor settings if you are trying to make the axis move at too fast a rate, the required pulse rate will exceed the rate at which Mach3 can output pulses to drive them - so you need to move up a stage from 25 kHz. Mach 3 can be set at different speeds, but it is advisable to use the lowest speed for your requirements.