[iGAK]

I ordered the NM-200 Series 2 AC spindle motor replacement kit and paid the shipping charges. When I called to place my order, Novakon said they would be able to ship a kit to me immediately. I ordered the kit with the understanding that I would be one of the first customers to install it and that there were no written instructions available at this time. They assured me that technical assistance would be readily available to assist me in the installation of the kit, programing of the Sunfar C300 VFD, and reprograming of Mach3. Their technical assistance was timely and excellent.

I had the kit installed and running within two days. I believe the kit can be installed in one day by following the written instructions and pictures that I will post herein.

I was able to run the AC spindle between 60 and 6000 RPM. The 60-6000 RPM variable speed range is accomplished without changing motor pulley belts. The torque at 60 RPM is strong and I cannot stop the spindle by hand. The spindle ran very smoothly at 6000 RPM. I am now able to cut, drill and surface plane steel at low RPMs. In other words, more aggressive cuts can be taken without bogging the spindle down. With the old BLDC setup, I was afraid to run the spindle below 4000 RPM for fear I would blow the BLDC controller board. Now, with the AC motor, I run the spindle as low as 150 RPM without fear of damaging the system.

The BLDC motor had virtually no torque at 400 RPM and had a maximum torque rating of 3.5Nm at 6000 RPM. The AC motor has a constant torque rating of 7.95Nm between the 150-6000 RPM range. What a difference (See the motor ID plates in the pictures below)!

I had been disappointed with the performance of the BLDC motor/VFD system. I had previously blown the BLDC controller board. Novakon sent me a replacement board under their warrantee policy. For over one year, I had been running my BLDC motor at 4000 RPM and above while waiting on Novakon to resolve the low torque problem.
Thank you Novakon, the low torque issue has been solved, and my upgraded NM-200 Series 2 Mill is one smooth running beast of a machine.

I believe the kit is a mandatory upgrade for NM-200 Series 2 CNC owners and that it is a good value if purchased by May 25, 2012 at the price of $695 plus shipping.

The AC spindle motor drive kit arrived via FedEx. The contents were well packaged as shown in the pictures below. My package also included some backordered tooling.

The AC spindle motor drive kit included the AC motor, steel mounting plate, DC-DC converter, motor pulley, Sunfar C300 VFD, cable connector, and miscellaneous wiring.

I will be posting detailed instructions on the Novakon AC spindle motor drive system installation as time allows.

[steveb946]

Why does the NM-200 spindle replacement cost $695 and the official upgrade for the NM-145 cost $1795?

Confusing!

[lindburg]

I purchased my 200 about year half ago. As long as I do not use a bit bigger than 1/4 inch the machine does a excellent job. since i have had the machine I have had to replace one stepper x axis motor and one computer tranformer. I had oil running all over the motor and called and talked to John about it about six months ago. He indicated they were going to replace the motor and apparantly they now have. I noticed in your post you were able to run the motor out to 6000 rpm Yet on their site specifications state max rpm a little over 2000 rpm. (speaking of new system) I would be interested in hearing all input as to anyone that has installed the new vfd and motor. Power milling success, size bits etc that they are not having problems with.

[t300]

Why does the NM-200 spindle replacement cost $695 and the official upgrade for the NM-145 cost $1795?

Confusing!

I wish Novakon would make that more clear as well. Side note - I could be convinced to spend $695 to upgrade my nm145. IF they had the units in stock and it wasn't prepay. $1795 AND prepay is not going to happen though.

[Novakon]

The difference between the NM-200 and NM-145 kits are very significant.

The changes to the NM-200 are mostly to the AC motor and VFD. Fortunately, the parts are form, fit and function and not too difficult to install.

The NM-145 has a more intense upgrade since the motors do not any longer fit internally in the casting and thus have to be mounted externally. In order to do this, we have developed a replacement casting cover/motor mount assembly. The other contributing cost factor is that the servo motor/driver are much more expensive than the AC motor on the NM-200. These are the highest quality servo parts obtainable from our manufacturer that they are well established. In addition, the driver chassis has to be replaced in order to mount the new components on it and to host some original parts.
Therefore this kit is more intensive in cost yet will be relatively simple to install with moderate machining skills and assistance from the Novakon team.

For more information, please contact [email protected] for any additional information.

Novakon Team

[UniqueMachining]

I purchased my 200 about year half ago. As long as I do not use a bit bigger than 1/4 inch the machine does a excellent job. since i have had the machine I have had to replace one stepper x axis motor and one computer tranformer. I had oil running all over the motor and called and talked to John about it about six months ago. He indicated they were going to replace the motor and apparantly they now have. I noticed in your post you were able to run the motor out to 6000 rpm Yet on their site specifications state max rpm a little over 2000 rpm. (speaking of new system) I would be interested in hearing all input as to anyone that has installed the new vfd and motor. Power milling success, size bits etc that they are not having problems with.

Lindburg

The Max RPM for the various series is listed below.
Series 1 (AC): 4500
Series 2 (DC): 6000
Series 3 (AC): 6000
I don't know where the a little over 2000 rpm came from.

As to the bit size I regularlly use 3/4" EM and 1-1/2 face mill with 0.050 DOC and 10 IPM (series 2). The key on series 2 (DC spindle motors) is not to use low RPM's e.g. less than 1000. You stated max RPM of 2000, so I assume you are running at that or a lower rpm. Try upping the RPM with an appropriate feed rate.

I usually run betwwen 2000-4000 rpm for milling and facing, 1500-1750 for drilling.

John

[hornby chopper]

Hi igak

looking forward to the rest of your post on the wiring and reseting of your mach3.

qestion 1 wher did you pull your power for the fan on the motor

I am thinking about using the power fed for the work light i dont use it i put the led ring light on mine .

any info on this would be great i am just going to start on my machine this week hade kit for about 2 weeks now

[iGAK]

I have finished the Installation Manaul for the NM-200 Series 2 AC motor upgrade kit.

However, I have been unable to post the zip files to this CNC zone thread.

Therefore, anyone who would like the files e-mailed to them, please pm me with your e-mail address and I will fordward the files to you.

The Installation Manual includes the following six chapters:

Part 1 Removing the existing BLDC motor control board

Part 2 – Installing the Sunfar C300 VFD

Part 3 – Removing the existing BLDC motor and installing the new three phase AC motor

Part 4 -- Reprogramming Mach3

Part 5 -- Programming the Sunfar C300 VFD

Part 6 -- Additional wiring of the BOB, VFD and AC spindle motor

Please note -- the installation instructions are for a NM-200 Series 2 CNC mill that use the CNC4PC C11G- MULTIFUNTCION CNC BOARD and the Gecko G203V STEPPER DRIVES

[lindburg]

Some had suggested that I check wiring from vfd to bob. Well I just went through and rewired it making sure good connections etc and now do not have that problem. One other problem that I have experienced since the new motor and vfd is that when the machine is first started up there is for some reason power being applied to the motor. Not enough to turn it but if you attempt to turn the spindle by hand it will not due to the power being applied. I have in past taken care of this issue by just entering in a command to turn the spindle and let it turn and what ever speed and than stopping it. I than no longer experience the power being applied to the spindle and that machining season can continue normally. Has anyone else experienced this problem.

[SCzEngrgGroup]

Some had suggested that I check wiring from vfd to bob. Well I just went through and rewired it making sure good connections etc and now do not have that problem. One other problem that I have experienced since the new motor and vfd is that when the machine is first started up there is for some reason power being applied to the motor. Not enough to turn it but if you attempt to turn the spindle by hand it will not due to the power being applied. I have in past taken care of this issue by just entering in a command to turn the spindle and let it turn and what ever speed and than stopping it. I than no longer experience the power being applied to the spindle and that machining season can continue normally. Has anyone else experienced this problem.

What you describe is probably a function of how the VFD is wired to the BOB, or the VFD configuration. There are three control signals: FWD, REV and AV. When FWD and REV are both HIGH (5V), the spindle will be off. If FWD is low (0V), and REV is HIGH, the spindle will turn CW, with the speed controlled by the analog voltage on the AV pin. Either FWD HIGH, REV LOW, or both LOW will give CCW rotation, depending on VFD configuration settings. The latest Novakon machines use the SpindleEnable output on the BOB to let FWD float HIGH when the spindle is off, and will turn on the SpindleEnable any time the spindle is commanded on by the PC, pulling FWD to GND, to turn the spindle on. The DIR signal from the PC is then routed to the REV pin of the VFD, and when it goes LOW, the spindle will rotate CCW.

In your case, I think you'll find the FWD line is being pulled LOW on powerup, causing the problem you're seeing. If you don't ever need to turn the spindle CCW (not sure I ever have...), you can simply wire the REV signal from the BOB to the FWD pin of the VFD, and change the settings in Mach3 so it sets the REV signal LOW to turn the spindle on. Otherwise, see if you can get the SpindleEnable signal to work, and connect it to the FWD signal on the VFD. Not sure if you BOB would even have the SpindleEnable output....

Regards,
Ray L.

Regards,
Ray L.

[lindburg]

Ray
Thanks for your response ...reverse can be used for threading...anyway the three control signals use for novakon are vc , fwd and grd. from my installation manual for upgrade to new motor and of course vfd. So what you are telling me is a little confusing. David

[Hirudin]

I have that same issue: when I turn on the machine the spindle does not turn easily. It also emits a high pitched whine. I hooked a volt meter to the VFD to act as a load meter - when it's whining the volt meter reads about 5v (IIRC). I've been using the same fix as well: start the spindle turning at any speed and stop it at any time (I usually stop it the instant it starts spinning). Once I do that the problem is gone. I've heard-tell of some kind of new connecting wire to go between the BOB and the VFD. Although I've been told about the wire, and been told that I can have one shipped ("mailed" really) to me, one has yet to appear in my mailbox.

[Whizbang]

Does anyone know where to get a state side equivalent of just this motor. I have the 4500 rpm on my series one and already have the vfd needed . I just need to find that motor or similar. I am guessing that the motor could just be dropped in and a hour or so for vfd reprograming.

Let us know how the upgrade turns out. 1500 rpm seems like it could really help high speed machining tool paths.

Thanks

[Dynoray]

Whiz, there are lots of options for motors and VFD's. I ended up using a WEG 3HP inverter duty motor and Teco CV7300 VFD with sensor less vector drive, it makes series grunt for 3HP at low RPM. I went with that motor as it was the only Aluminum frame motor I could find at the time and I was concerned about the extra weight on the spindle. Turns out, the extra weight (along with the power/torque) made the machine better in everyway, much better vibration dampening. Down side is, that WEG motor is only rated for 5400 RPM. I have ran it as high as 6900 RPM but it has ZERO power there, only usefull for ball mill profile finishing but with, I'm sure, MUCH shorter motor life.
I believe that WEG motor is 50's lbs (would have to look for sure) but if I was doing it again, and I think I will change anyway. Marithon have a 3HP inverter duty motor rated for 7200RPM with constant HP to 5400 ish RPM and it weighs 63 lbs. That might shorten the spindle bearing life but then we can just upgrade the spindle bearings or change to an 8000 RPM BT30 spindle.
We have an older NM200 Pro, when they came with the BLDC spindle motor and Geco drivers. After upgrading the spindle motor, VFD and getting rid of the geco drivers, adding bearing ball screw mounts and a few other upgrade, it's been a good little machine.
Next upgrades are: Higher RPM spindle motor, BT30 spindle, better ball screws and better linear ways on the Z and servo's.
Even with the 50's lb motor on the spindle, with the new drivers we run 250"/min rapids.
Ray