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Author Topic: Mach3 limited step pulse frequency problem  (Read 527 times)

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Mach3 limited step pulse frequency problem
« on: October 29, 2018, 07:02:35 AM »
I am using Mach3 on Windows 7. The hardware is A4988 (stepper driver) and a small stepper motor taken from photocopier. I am using 12VDC and printer port.

The Motor Turning setup is:

Steps per unit >5080
Velocity > 6
Acceleration > 0.6
Step pulse (1-5 us) > 0

This setting works fine. But whenever I try to increase Velocity e.g. 10 or 15 or 20. The motor turns with only Velocity (6). I mean that I increase the velocity in Motor Turning Setup, but in practice it does not increase and it remain 6. I also tried to increase Step pulse (1-5 us) e.g. 1, 3, 5. But the velocity does not increase more than 6.

I also used 555 timer based step pulse generator in place of Mach3. When using 555 timer based step pulse generator, the motor turns with more than 6 Velocity and the motor run faster.

I could not figure out the problem. Using Mach3, the velocity should increase. Is there any problem with Mach3, printer port or computer itself?

Offline Tweakie.CNC

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Re: Mach3 limited step pulse frequency problem
« Reply #1 on: October 29, 2018, 08:16:53 AM »
How do you know that you are only jogging at a velocity of 6 ?

(If you are looking at the FRO and Feedrate DRO's on the main screen then they show 6.00 until such time as a Feedrate is set - this does not mean that you are jogging at 6.00).
KEEP SAFE !

Offline ger21

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Re: Mach3 limited step pulse frequency problem
« Reply #2 on: October 29, 2018, 08:49:24 AM »
To clarify, the default feedrate in Mach3 is 6 units/min. Try setting a higher feedrate using MDI.
Gerry

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