Hi guys. My 10 year old secondhand RATTM MK100 motor VFD suddenly decelerated the bit and started throwing error codes mid-cut yesterday, so I suspect that it is bad and needs to be replaced. My spindle setup is 1100V, 2.2KW water-cooled spindle. The error codes were Err02, Err05, Err18 and Err40, despite re-starting and rebooting, and trying both INTERFACE and OBC sending both a GCODE file and simple Spindle on/off commands via laptop. The Spindle would re-start then just decelerate and stop then throw error codes at first, so then I removed both the Blackbox wiring and the spindle U/V/W harness and re-booted everything and changed the VFD to manual potentiometer control and it still would just throw error codes with nothing wired to it at all. I was just getting to the good part of the Grand Canyon in hour 3 of the 18 hour carve too! This seems like a good place to ask about how to correctly wire up the replacement. I have the Huanyang HY02D211B VFD on order, and will try the swap when it comes tomorrow to see if that gets me back up and running. I watched the OPs video, very helpful thank Josh. I wanted to confirm things here. 110VAC line voltage grounded 14ga pigtail plug: BLACK---->R terminal WHITE-----> T terminal GREEN-----> 9 terminal (Looks like Josh does not do this in the YT video in Post #1? Why not?) Spindle Motor (Huanyang 2.2 KW 110VAC Water Cooled) U / BLUE wire---> Motor #1 V / BROWN wire ----> Motor #2 W / BLACK wire ----> Motor #3 Do I run a separate GREEN wire from Motor aviation plug pin #4 to a true earth wire connected to a lag bolt in my shop foundation wall bolt? My machine has been running fine for 8 months without one but it is a good idea to do this right? And is it necessary tonot just run the wire to the VFD ground #9, but to an actual earth? Black Box Connections / VFD Control: TOOLHEAD: GROUND---> GREEN Wire to VFD Terminal (ACM) 0-10V----> RED Wire to VFD Terminal (VI) Jumper Wire FOR to DCM VFD Settings: PD005=400 PD002=1 PD070=1 PD072=400 PD144=3000 PD008=110 Just remembering now that I also previously had a physical on/off "light switch" wired into the VFD to act as a separate safety shut-off for the spindle motor....so I'll need to replace that in here somehow too. Thanks!
Look up the error codes in your VFD manual, determine what they mean first. Depending on what they say - it could be damaged wiring between VFD and Spindle, or bad bearing in spindle causing strain, or damaged windings in spindle. Far less likely the VFD itself (usually, but look up the codes first) - VFDs usually outlast spindles (usually)
The manual that I have is photocopied and in poorly translated Mandarin, of course. I think it says Err02 = Acceleration Overcurrent (possible low voltage) Err05 = Acceleration Overvoltage (high input voltage) Err18 = Current Detection Fault (Replace Hall device and/or Drive Board) Err40 = Wave-byWave limiting Current Fault Question - if I bench test the VFD, why would it give a low voltage error number 2 with nothing connected to it at all? Wouldn’t that indicate that something inside of it is bad? Edited - changed to relate actual codes from manual
Also I do have a spare spindle motor that is brand new replacement of the exact one on my machine. I was reluctant to wire it up until I can confirm that the VFD isn’t fried because I don’t want to ruin a brand new spindle.
Any change the voltage config parameter was changed to 220v? Up to you at the end of the day - just like you are scared of damaging a spindle, same held true in my thinking if the clues point to spindle perhaps... But if the codes check out, then go with that
Can’t see how that would have changed… As far as further bench testing with a digital multimeter…what should I see from the UVM terminals with the VFD in potentiometer control mode and 400hz as frequency when I press RUN?
If you have to ask how, perhaps you shouldn't just a saying, but somewhat appropriate. Don't do that! Stay away from the mains voltages. You CAN measure the resistances of the spindle coils (no power, no wiring, measure U-V, V-W and W-U resistances - all three should be close to each other) but don't try any voltage readings, particularly not high voltage, worse so on a suspected damaged VFD
Duly noted. In the interest of learning, what comes out of the UV and M terminals? I would like to deepen my understanding of how the VFD controls the spindle motor, preferably without any magic smoke.
Three phase power but with the ability to vary the frequency (with a healthy dose of monitoring, the VFD checks things like current draw, voltage rise, load resistance, Back-EMF from the undriven coiks, and a host of other parameters) 50/60hz AC Single Phase (or 3-phase for larger VFDs) > Rectified to DC > Converted back to 120-400hz AC 3-Phase Being able to vary the frequency, changes the motor speed. VFD spindles are just 3-phase motors, tuned to perform at higher frequency. Youtube is a healthier way of learning than experimenting
We'd still prefer to NOT host videos / link like those. We don't want to encourage people to take risks. I might be editing the links out, you have to understand. "Call your electrician" is good advice even for clued up people, much more so for a newbie stumbling on this thread in the future
Understood completely. I already texted my electrician friend to come over after work tomorrow to look at what I've got going on....
@Peter Van Der Walt what are your thoughts on adding a dedicated ground wire to the #4 pin on the spindle? Should I plan to run this ground wire to the Huanyang VFD Ground terminal (#9), or run it to Ground separately from the VFD?
Spindle should normally be grounded for safety yes. Spindle body > PE terminal in VFD > Mains Earth in wall plug Did you check continuity between pin 4 and the spindle body? Cheap chinese spindles often lack the internal wiring on that (;
Josh how come you specify PD144 = 3,000? Shouldn’t that be 24,000 (Pd144 in the Huanyang manual is “Rated Motor Revolution”. Edit: also, and maybe @Peter Van Der Walt can speak to an answer…in Josh’s video he appears to leave the Green ground from his 110V mains pigtail hanging in the air…should this be connected to HY terminal 9 (Earth)?
Also I have another follow up question: my old VFD came with this card instructing the installing engineer to loop the three UVM cables from the spindle around a vinyl covered iron ring as close to the VFD as possible: This was done on my CNC when I bought it: There is no mention of this in the Huanyang VFD directions – so is it safe to assume I don’t need to do this with this new VFD?
There is continuity between pin #4 on my Spindle and the outer case of the spindle housing. I don’t like the fact that the Huanyang spindle directions do not specifically call out wiring motor post #4 to VFD #9, but I’m going to do that anyway.
Rightly so. Depends on the use case. VFDs aren't just for CNCs. If you have a borehole pump running off it, you DON'T want to earth it If its in a more industrial setup, you also wouldn't Earth it like that, it would be a star ground complying with OSHA and Electrical codes. Different ways to do things apply, thus the manual leave it up to the...
Peter – if I wanted to put in a safety switch to be able to turn the spindle off manually, would I wire the switch into the 0 to 10 V wire coming from the black box to the VFD?
Rather the "arming" side (COM to FWD jumper, replaced with switch) but going to be honest here, I am super paranoid when it comes to that, I'd personally rather cut the power to VFD - while changing tools, I really don't want an accidental start...
This is a big factor for me because when I pause a 13 hour 3-D finishing cut, I need to be able to turn the spindle off overnight and restart in the morning to resume. edit: unless there’s a way to modify the black box GRBL Paramus to turn the spindle off when the program is paused…?
So to make sure I understand you correctly - you would wire a switch into the mains 110V that feed the VFD?
Safer (paranoid maybe) Not sure if that will play nicely with your Pause plans though - you'll have to test
For sure. I am coming from the ShopBot world, when I pause their machines, the code stops, the bit lifts 1" off from the workpiece and the Spindle spins down, and you then have the option to insert commands as needed, or mess with the dust boot etc., then you click "resume", then hit a physical "START" button on the desktop, the spindle powers up back to specced RPM, then you click "OK on the screen with a mouse and the program goes back to the workpiece & resumes where it left off. In the Open Builds world, what I have been doing for the last 9 months is hitting "Cancel/Abort" on INTERFACE, then turning off the spindle with a physical switch wired into COM on the VFD), unplugging the VFD from the mains outlet, then returning in the AM, re-plugging in the VFD, turning the switch back on to spin the spindle up to RPM, then clicking Resume on INTERFACE.
Grbl does not stop on "pause" (Incorrect naming, its actually FEEDHOLD - correctly so it only stops feed, not tool) Grbl with a Door switch can stop the spindle, but normal feedhold does not. See the Grbl Wiki to learn more As for the others, see if it works same with your new VFD and take it from there - we can only suggest, how you implement it is up to you, your needs, what you can and cannot do withing the confines of the VFD itselft etc
So Peter what was up with the ring of wires/iron ring coil on my old setup? Was that meant to be an EFI filter? Why don’t the new VFDs spec this out durning install?
