Spindle and VFD (Variable Frequency Drive) Setup Part 1 

Thanks for the info!

Some of the spindles don't have the 4th pin connected to the body of the spindle. If your machine is grounded, you don't need to connect the 4th pin and some manufacturers will warn the end user to not use the 4th pin if the machine is grounded and the spindle is conducted to this ground (via the metal on the machine).

Thanks. I have been using shielding a little while after I made this video. Initially, I was testing the PWM from the computer to the VFD and noticed the value jumping around like crazy. Now I shield the spindle cable and I also shield the PWM signal cable. I've also seen some folks actually use ferrite to assist with the PWM signal cable. The wires are coiled around the ferrite to create inductance. I'm not sure how this helps, but if you or anyone could shed some light on this, I think it would benefit others.

Thks!!

@@PatrickHoodDaniel The ferrite core is known as a load reactor but it’s just an inductor. Motors on VFDs create a lot of harmonics and reflected signals (voltage spikes coming from the motor back into the VFD). These spikes can reach thousands of volts so the load reactor is there to limit the spikes and protect the VFD and motor

: :.((

The spindle must be earthed (grounded) for safety! Without en earth, a small breakdown in spindle winding insulation can cause the body of the spindle to become energised with a couple of hundred volts and killing someone. With proper earthing, the faulty spindle will trip the fuse, CB or the drive unit, keeping everyone safe and you knowing your spindle has an electrical fault. Earthing/grounding is essential to safe operation!

That is correct. I should have mentioned that I'm using the neutral as another live where I am using L1 and L2. I appreciate this comment as I am pretty good with the digital electronics side but I am not strong in the electrician side. I make this clear on the spindle page as I have a disclaimer to seek a professional electrician for connecting a VFD. This disclaimer is here under the instructions section: www.buildyourcnc.com/item/spindle-inverter-2!2kw-spindle-vfd

So did you cut the plug off and install a 220v plug?

😮😮, wow, 😳😅, that's news to me too, I didn't know that. Now I know why I thought cable does not work 😂😂. M in Africa, 220V😊

Yes, here you go: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-aD3_0NmUowk.html

@@PatrickHoodDaniel Thank you!!

@@Jcreek201 You are welcome!

He used a standard 110v plug but wired it to carry l1 and l2 on white and black with the green acting as neutral, I would have used a NEMA 6-15P plug and the correct wire colors but essentially his works. However it could accidentally be plugged into a 110v outlet.

You only need the Rpi to output a PWM between 0-10V and use the VI and ACM terminals in the VFD with this PWM output. PWM to VI, RPi gnd to ACM. If you need a voltage reference of 10V, you can use the 10V terminal in the VFD.

@@PatrickHoodDaniel THANK YOU SO MUCH YOU ARE AWSOME!!! BLESS YOU

Just swap two of the three wires that connect the spindle to the VFD.

That is an overcurrent message. I would first measure the resistance between the three pins on the spindle to see if the windings have a short. Do do this, use a multimeter set to ohms, measure between pins 1 and 2, then 2 and 3 and finally 1 and 3. Make sure to do this with the cable off because the cable may have a short by itself. If the measurements are the same, the cable may be bad. It is difficult to test a cable because the issue can show itself when the cable is laying differently, so it would be best to replace the cable. If you are experiencing this problem with a totally new VFD and spindle, you may want to reduce the ramp up and deceleration (make it a longer time).

Yes. You can use the M3 to run forward and M4 to run reverse. M5 to stop both.

You will need to connect the VFD through two outputs on your controller.

Thank you very much Sir!

Hi Sir. Do you have a video or instructions how to wire and pins set connected to control board ? Thanks for your help!

Yes, we do. We recommend that the Protective Earth be connected to the housing of the spindle typically to one of the screws of the back round connector. Thanks for pointing this out.

I would connect the ground on the VFD end instead, unless the machine body has a better ground connection than the one in the mains cable.

Thank for the video. One other thing to point out (you will already be doing this if using shielded VFD cable) is that the green wire should never be used for a current carrying conductor (power wire).

A VFD is required if you use a spindle. If you use a router, a VFD is not required.

@@PatrickHoodDaniel Oh, well, now it's starting to make more sense. I thought a spindle was just another term for a router that's made specifically for use with a CNC machine. Can you cool a spindle with air? I was looking at a 1050 FME-W DI spindle.

Actually, aren't these Kress/AMB spindles more like a router in the sense that they aren't water-cooled and don't need a VFD or am I wrong?

@@tomjoad6993 You can cool a spindle with air. There are air-cooled spindles, but I don't sell them. I like water-cooled spindles because there is no air movement pushing the dust and chips in the shop. Water-cooled spindles are great because it's less noisy (no blower fan) and the vacuum can work more efficiently removing all of the chips and dust. Water cooling is not a big deal to establish and it cal all be compactly fixed on the Z-axis. buildyourcnc.com/item/pneumatic-hydraulic-spindle-inverter-cooling-water-pump-reservoir-fan-radiator-g14fittings-silicone-tubing

@@tomjoad6993 I don't have very much experience with Kress or AMB. From what I know, Kress are very much like routers and don't need VFDs.

I've used a couple VFD's for other purposes and I'd say your assumptions are correct, just wall power -> vfd -> three phase motor. Nothing else (besides the appropriate kind of wires in between).

I would recommend using 16 AWG, but 18 AWG has worked for me. Some spindles and VFD come with 18 AWG cable. The wattage is divided by the three phases, so the actual current on each wire is 3.333 amps.

I use a 3000W transformer for anything with load. The video here is only a 300W transformer because I am only testing the spindle and VFD with no load on the spindle.

Yes. The given freq was its max modulation of 400 Hz to deliver that rated 24K RPM.

Here is one of them: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0SLFuM4tzuU.html

This inverter is for a maximum of 2.2kW.

Yes, this is one of them: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0SLFuM4tzuU.html

Check out the CNCZone. I saw someone posted the working settings for that model.

Since the Spindle is 2.2kw would an ST-3000 work be a better choice

Yes, you would definitely want the 3000 watt version if you are going to operate a 2.2kW (2200 Watt) spindle and VFD. Mind you that I have not tried this in production. We have a dedicated 220V outlet in our shop.

Thanks.

I could be wrong, but I believe most people do not control it that way. They turn it on manually, then run their cutting program. I've seen this done in many videos that way.

Indeed - they generate three phases by converting incoming AC to DC and use PWM/IGBT's to generate an approximation of 3 phases.

You're welcome!

Compraste un trifásico a la entrada y tú tienes monofasica

Mide el voltaje entre las terminales fase y neutro y si te da 220v conectarlas al vdf en terminal r y s una cada una

Are you referring to the 4th pin at the back of the spindle?

yes :)

From the factory, that pin is not connected. Because it is a metal casing, we connect that pin (from the back of the connector, not the connector on the spindle) to PE (protective earth). I'm not sure if this is required which is why we require our customers to seek guidance from a professional electrician.

So I don't have to solder additional wire from the inside of the pin to the body of the spindle ?

I think it's from from an obscure 1981 sci-fi horror movie ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1qCszP4HI7U.html, en.wikipedia.org/wiki/Scanners#Head_explosion_effect

Its called an aviation connector

​@@lindseyaltman4288 I actually managed to find the name but thank you very much for your answer :)

Thanks for the expert advice. I currently use shielded cable and I add a 4th wire to the body of the spindle. Is that what you would recommend? What gauge would you recommend for 2.2kW spindle understanding that each wire would carry 1/3 of the current.

Great! I would definitely recommend the protective earth connected to the body of the spindle motor. I think 16 ga would be the minimum size you'd want to use on a 2.2KW spindle. The 2.2KW motor will draw roughly 10 amps at full load, which is 10 amps on each wire, 10 amps total. You wouldn't divide 10 amps by 3 to get the current on each wire, or multiply 10 by 3 to get total amps. A three phase motor is sort of like 3 single phase circuits, only each circuit is 120 degrees out of phase with each other. Also, I re-read my original comment and it looks a little abrasive. I apologize for that.

@@shampyswoodworking525 Thanks for the clarification. I was under the assumption that since the total drawn from the spindle was 10 amps (2200W/220V = 10A) and if the total current was traveling through three separate coils, that would be divided by three, making each wire requirement at 3.34 amps.

@@PatrickHoodDaniel no, that isn't the case. If you look at a 3 phase motor's nameplate, you'll see a bunch of ratings and data for that motor. One of the numbers will be labeled FLA, which is full load amperage. If the FLA rating is 10 amps, each leg will draw 10 amps when the motor is doing it's rated KW or horsepower worth of work. We would describe that as 10 amps, 240 volts, three phase. Likewise for a single phase 240 volt circuit in your house... same idea. Your dryer might have a 50 amp, two pole breaker feeding it. That breaker is essentially 2 single pole breakers tied together, each pole rated at 50 amps, not 2 poles at 25 each. So the motor's wire size needs to be sized to it's FLA rating, in this case a 2.2KW motor at the given voltage will be around 10 amps (A little less than 10 actually, because in the US the single phase voltage will really be 240V).

Can you point out the error?

I use a step down convedrter that you don't see in the video. This converter accepts standard three prong plugs that appear like the ones used in 110V. I am American. I live in Florida.

He's referring to it as a CNC spindle. It's a term used in the CNC industry for the electric motor that drives the milling/cutting tool. Same word, different context.

Add the ground.

Please elaborate.

Nah, it's a 240v, it is just wired up weird. He used a normal 120v plug, but when he plugged it into the transformer, it basically made the hot (black) the first 120v line, the neutral (white), the second 120v line, and the ground (green) the neutral. Building inspector would have their asses...

This was from a movie released in 1981 called scanners.

Thanks for the comment, Tony. I typically take off the nut and collet when doing this. We know the dangers. Thanks for pointing this out so others know.