S30 spindle Speed not Correct?

Just installed my new S30 spindle and noticed that the spindle speed does not match Mach 4?

If I adjust it in Mach 4 with the spindle override it will move faster and slower, but if I enter the speed in the ‘Spindle Speed’ box it is not correct. Even worse, if I run code, it doesn’t match what is in the code.

Anyone else experience this?

What spindle type did you select in the Configuration?

I selected the 8HP per the directions from CNC Depot.

Uh, that doesn’t sound right. But if that is what they told you. Ok. Mine is not set up like that.

The S30 has a max of 18,000 RPM though. It will not exceed that speed and you will tear it up if you maintain that speed without doing a full warm-up (or for that matter a break in cycle).

Yes, I did the break in cycle and a warm up before using. I have only had it up to 16000, I think, and plan on using that speed for most of my cuts.
4000 and 16000 when typed into the spindle speed box look and sound exactly the same. Not sure what’s going on?

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You have to open up the screen set and alter the scripts. Those numbers are because AvidCNC set the speeds to their spindles.

I would copy the AvidCNC profile and rename it. That way when they update the don’t blow you up. I would also copy their screen set and rename it as well. Then alter the hard coded minimum and maximum values to fit the S30.

All that said, the frequency that Mach4 is setting on that VFD might not be correct and it says it is at 15,000 but that isn’t what you are getting. The VFD can also be setup incorrectly.

I would call Alex Burt and verify that. When in doubt, factory knows best.

I did message Alex about it and it turns out my spindle was running in the wrong direction. I had to move around a couple of wires, now it’s working fine.

yep, good news! Still make a separate profile from the AvidCNC and make a screen set as well to set those min and max numbers so you don’t blow that S30 up on accident.

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I’ve found myself in the same scenario with the S30 spindle.
Having to learn coding via this equipment has been quite the trial by fire so please bear with me.
I’ve got the profile and screenset copied and renamed.
Where/How will I know I’ve found the hard coded values?

I though cnc depot only made 3hp s30 units. Been a few times I would have liked a couple more hp. I may have to see what the cost is for an upgrade.

CNC Depot can sell you a HITECO QD-1F spindle, which is one of the largest that you can run on an Avid. It’s ~5hp with the given VFD.

You shouldn’t have to edit or code anything. If you set it to use the 8hp Avid spindle, then the VFD should work properly for the S30. You should be able to look at the VFD when the spindle is on and see the frequency it is running, and that should be the basis for the speed.

Did you call CNCDepot? They are very responsive. I would start there first.

They have changed the documentation and spindle / VFD setup since I installed mine back in 2019.

Also, they have new break-in and warm-up instructions that are specific to each model.

Yes, the machine configuration is set for the 8.7hp spindle per the instructions.
Double checked the hardware wiring.
ESS setup guide was double checked for oversights - I suspect I may have missed something there but I’ve tinkered with every applicable option I’m aware of.
Graphing the data shows a linear relationship where the rpm overage % is decreasing and there will eventfully be a convergent point (perhaps @ 18K rpm?).

Are you getting getting 18,000 RPM at 300 Hz? Looks like you will based on the numbers. I don’t know what the min RPM is for the S30…values may be off at low RPMs just due to the way the VFD works. I’d suspect the issue is the VFD programming/values. A lot of spindles have a min RPM value. Assuming it is linear, for a 300 Hz spindle (at 18,000 RPM max), 100 Hz will give you 1/3rd the max RPM, which is 6000 RPM. So, the VFD’s values seem correct…which does mean something is wrong with the setup in Mach 4.

How are you checking RPMs? This makes me curious about mine being off.

EDIT: I am not an expert on this…and just tossing out some ideas.

In case it’s not obvious, the F-value is typically Hz, which for the S30 is rotations per second. The RPM will always be 60 times the Hz.

F138 * 60 = 8280
F244 * 60 = 14640


All good Corbin. I appreciate your interest.
Manufacturer claims there is no minimum RPM value on the S30 and that some customers drill using as low as 1500 RPMs.
I am checking RPMs with a digital tachometer. It’s cheap but has proven consistent. The reflective tape is applied to a collet nut with a matte black finish.
I think I’ve been through all the different variations possible within the Configure: Control and Configure: Plugins: ESS windows.
The following are the original overage RPMs from earlier in the day:

The slightly higher RPMs you see in this data set is a result of the MinRPM in the Control Configuration being set @ 0.00
When this value is set @ 1000.00 then I get the slightly lower RPM threshold in the former chart.

An additional observation is that these two datasets seem to match the extreme ends of the carrier frequency range (8.0-12.0) for the spindle: 8.0 & 12.0 precisely.

When the system is idle the VFD reads F100
When asked for 1000 RPM spindle speed in Mach it bounced between F100/101 @ 6030 RPM
Sooo… idle @ F100?

There’s usually a separate “enable” or “forward” signal that must also be active to switch from stopped to the commanded frequency.

One last observation, perhaps unrelated, but needing acknowledgment in the off chance it is…
I went to change the the default status of my screen’s Keyboard Jog button in the PLC script and found the needed code change was already in place but not executing. I found the script to have some bugs. Strange b/c I’ve never been in there. Tried the same in different profiles and screensets to no avail.
I have zero interest in installing all the software again from scratch, but I also don’t want to waste everyone’s time chasing a ghost.
Again, maybe not related, but say the word and I’ll gladly take one for the team.