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Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 10:19 am
by ericbowman
Thank you for the vocabulary, I didn't know they were called ampacity tables.

What are the temperatures and the type acronyms below the temperature on the tables?

Image

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 11:36 am
by tblough
The temperatures refer to the maximum allowed temperature the wire and wiring components are rated for. Current generates heat in wires so wires rated for higher temperatures can carry higher currents.

You need to use the LOWEST temperature rating of all the components in a circuit to determine the column to use. If you use 90°C wire, but connect it to a 60°C rated breaker, then you must use the 60°C column from the ampacity table.

Again, a Google search would have told you what the acronyms were. They refer to the different types of wiring and insulation systems. THHN is "Thermoplastic High-Heat Nylon", MTW is "Machine Tool Wire", SE is "Service Entrance" cable, etc.

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 3:39 pm
by martyscncgarage
Eric,
No one is going to make fun of you. Actually we want to help you succeed. You do that by putting yourself out there.
If you follow this post and provide all the information, including pictures, we can take a look and make suggestions.
viewtopic.php?f=60&t=1043

Provide the make and model of the spindle motor, including a picture of its nameplate showing the voltage and current information.
Provide the make and model of the VFD including link to the manual
Make and model and manual of the drives.

Honestly, it would have been better for you to keep with your original build post, now you have information in two different places.

The more information you can provide the better suggestions we can make.
Marty

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 3:43 pm
by martyscncgarage
ericbowman wrote: Tue Nov 30, 2021 10:44 pm For 220v 20amp wiring what gauge do I need? Where would I buy 3 shielded wire in that size? The highest capacity stranded, shielded wire I see on Amazon is 16 awg which seems a little thin.
Where are you getting this information from? You are asking a generic question, not a specific question, as it applies to us.
As an electrician by trade, I will answer your question as posted. You need #12 copper wire for a circuit connected to a 20amp overcurrent device.

BE SPECIFIC, what are you connecting, show the nameplate of the device. See my previous post.
Marty

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 9:15 pm
by ericbowman
Here is a photo of my acorn and gecko controllers. There might be some noise due to EMI but they move fine. I only have trouble when I fire up the spindle.
XYZWiring.jpg
Here is a photo of how I have the VFD wired in. I know it's janky wiring, but it's quite far away from any signal wires so I am honestly surprised that I'm getting any interference from that part.
VFD Wiring.jpg
I'm going out there now to work on it, I'm planning to just tidy things up, take more detailed photos with a few annotations and upload them.

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 10:26 pm
by Sword
Aren't these the same drives as are having issues here? viewtopic.php?f=60&t=6477

A pattern perhaps?

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 10:42 pm
by martyscncgarage
Sword wrote: Wed Dec 01, 2021 10:26 pm Aren't these the same drives as are having issues here? viewtopic.php?f=60&t=6477

A pattern perhaps?
They are, but Eric says his stepper motors are running and are accurate. Correct Eric?

Marty

Re: z axis moves when spindle turned on

Posted: Wed Dec 01, 2021 11:44 pm
by tuffduck
Hi, I am having issues with my g214's moving on there own when I start cnc12. Have you had this problem? What revision version are your drives? Thanks

Re: z axis moves when spindle turned on

Posted: Thu Dec 02, 2021 1:33 am
by drdennis
I know it's janky wiring, but it's quite far away from any signal wires
You don't know if the interference is through the air or conductive via your wires. Please note that the noise is as likely to be conductive (on your wiring), as it could be electromagnetic (in the air). No shielding will help if the VFD is pushing noise into your shop AC power distribution (shop outlets).
I am surprised that the extraneous movement is constant rather than only on power transients (which is more common), so my first guess (obviously I don't know for sure) would be that something in your setup is seriously wrong (voltage levels, ground returns, etc.), with the noise just making things worse.

You should watch this to get an idea how serious a problem EMI is and how difficult it is to combat it even for well-seasoned electrical engineers.


Rather than experimenting with wires without having any data to guide you, I would recommend you do your homework and follow (to the letter!) some well-designed machine wiring instructions. It is very difficult to diagnose and fix EMI issues with the right instruments; it is impossible to fix it while guessing. Your best bet is to do it right to begin with.

Re: z axis moves when spindle turned on

Posted: Thu Dec 02, 2021 9:33 am
by Gary Campbell
Do you have a closeup of the yellow wire going into and out of the VFD? IS it shielded? Specs?