Pulse in setup

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usinaet
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Pulse in setup

Post by usinaet »

Hi
The pulse choice in the setup is affecting what component on the system ?
100000 to 400000 what would be affect on the use of my machine.

thanks
Alain
martyscncgarage
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Re: Pulse in setup

Post by martyscncgarage »

usinaet wrote: Sun Feb 28, 2021 11:46 am Hi
The pulse choice in the setup is affecting what component on the system ?
100000 to 400000 what would be affect on the use of my machine.

thanks
Alain
Your axis drive. It is important to look at the specifications for your axis drive and see what its max Pulse Input Frequency is. Set it at or below that value.
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
Richards
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Re: Pulse in setup

Post by Richards »

I run my DM542 stepper drivers at 100,000 pulses per second and my ClearPath servos at 400,000 pulses per second. Sometimes the manufacturer uses maximum steps per second in the specs and sometimes the manufacturer uses a minimum pulse width. To find the pulse width, divide 1 by the steps per second, i.e., 100,000 steps per second = 1/100,000 = 0.00001 seconds per pulse (10uS). 400,000 steps per second = 1/400,000 = 0.0000025 seconds per pulse (2.5uS).
-Mike Richards
usinaet
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Re: Pulse in setup

Post by usinaet »

is the answer should look like that
●在采用集电极开路输入方式下,最大输入脉冲频率200kHz(kpps) 。Under the open collector input mode, the
maximum input pulse frequency is 200kHz (kpps).
Richards
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Re: Pulse in setup

Post by Richards »

You could probably use either 100,000 or 200,000 with that driver. Unless you have some reason to need 200,000 pulses per second, why not just use 100,000?

If I've done the math correctly, even if you had the driver set to 16:1 (16 pulses per full step), the motor would be able to turn 1,875 RPM. (100,000 pps / 16 = 6,250 full steps per second. 6,250 full steps / 200 steps per revolution = 31.25 revolutions per second. 31.25 revolutions per second X 60 seconds = 1,875 RPM)
-Mike Richards
usinaet
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Re: Pulse in setup

Post by usinaet »

Ok you confusing me !
I have a ratio on my servo drive and on the software from centroid ?
The only reason my acorn is set to 400 000 is because it giving me more max speed , I can set it to 400 rpm at max .
If I use the 200 000 it lock me at 295 or something around that .
And what about the ratio on my drive .....
Thanks
cnckeith
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Re: Pulse in setup

Post by cnckeith »

usinaet wrote: Wed Mar 03, 2021 11:03 pm Ok you confusing me !
I have a ratio on my servo drive and on the software from centroid ?
The only reason my acorn is set to 400 000 is because it giving me more max speed , I can set it to 400 rpm at max .
If I use the 200 000 it lock me at 295 or something around that .
And what about the ratio on my drive .....
Thanks
post a fresh report.zip for good support so we can see your settings
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
Muzzer
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Re: Pulse in setup

Post by Muzzer »

295rpm is about 5 revs/sec (Hz) and you have 400,000Hz pulse frequency. That's implying your motor and driver are set to around 80,000 pulses per rev. I don't know what ballscrew pitch you have but a 5mm or 5tpi pitch would give an effective resolution of around 0.06 micron or 2.5 millionths of an inch.

Even if I got my sums slightly wrong, you get the point. You need to reduce the pulses per rev of the motor, not turn up the pulse rate. Try something closer to 5000 pulses per rev which would give you a nominal resolution of 1um with a 5mm pitch ballscrew. Your machine will never get anywhere near that accuracy but it keeps the numbers simple.

The ballscrews have a maximum rotational speed, so be careful not to exceed that.
martyscncgarage
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Re: Pulse in setup

Post by martyscncgarage »

To create a report
F7 Utilities
F7 Create Report
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
usinaet
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Re: Pulse in setup

Post by usinaet »

ok I will send a report tomorrow .
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