Hua Jiang/Huanyang + VFD Combo - Sudden loss of torque
Xzero machine, tuned and running great for 3+ years now. Until very recently the following is happening
Note: Spindle is a 2.2 KW - 400Hz ER-20 collet, VFD is a 230V, 15A from the same mfg as far as I can tell - the common package available widely across the web.
Problem as of last week:
- loss of torque/power during cuts
- RPM is visually and audibly slower when engaging material - despite VFD readout remaining constant
- example cut parameters (3/8" upcut spiral, .125" pass depth, 16000 RPM, 70 IPM feed) *** these settings are an example of a VERY conservative cut for this machine, in actuality we've run the machine much faster than this
- I've gone through the VFD parameters and nothing is out of the ordinary there - nothing changed since setup
- Spindle is not overheating
- Just noticed that the fan on the VFD is no longer operating (could this be an internal heat issue? - perhaps there is an internal safety limiting torque upon fan failure?)
Has anyone experienced the above symptom(s)?
Can anyone suggest any troubleshooting steps... i.e. VFD voltage/amperage checks?
Is it possible there's a loose wire or something internal in the VFD that could be faulty, resulting in poor communication to/from the spindle?
Thank you!
Re: Hua Jiang Spindle + VFD Combo - Sudden loss of torque
Did you check the resistance from the output on the VFD to the motor? I would turn off and lock out, then pull the wires off the VFD going to motor, and the wires at the motor coming from the VFD. Shouldnt be more than .08, more like .02 to .04. Also the fans not turning on the VFD would worry me. I would find out what the deal is with that. There are a lot of places you can send it in to for inspection. Hope it all works out
Re: Hua Jiang Spindle + VFD Combo - Sudden loss of torque
Thanks Joshua,
Checked resistance, 0.04 across the board. Going to try disassembling the VFD to investigate the fan issue now.
Re: Hua Jiang/Huanyang + VFD Combo - Sudden loss of torque
Are you sure the fan ran before? Some of these have 'smart' fans that only run when the unit is warm enough to need cooling.
Re: Hua Jiang/Huanyang + VFD Combo - Sudden loss of torque
Skrubol, yeah it used to run all the time.
Anyway, I replaced the VFD and the new one runs its fan continously upon power up. No change in performance occurred here.
Then I replaced the spindle and we're back up and running at full power.
New spindle noticeably quieter without load. From everything I've read and experienced in the past, failed bearings would be extremely obvious. This wasn't the case here (spindle ran fine at any RPM and relatively quiet without load)
Perhaps the windings are shot. Or some kind of short happening inside the old spindle? I notice that the new spindle passes coolant MUCH easier.
Anyway, I'm back up and running. If anyone wants to suggest troubleshooting the old spindle, I'm open to it. I.e. could it still be bearing related despite a lack of horrid noise?
For anyone reading this just trying to get back to a state of normal cutting, I recommend just buying a new kit. For $500 it's worth just replacing and holding onto your questionable parts as emergency backups.
Re: Hua Jiang/Huanyang + VFD Combo - Sudden loss of torque
Quote:
Originally Posted by
jwhil
Skrubol, yeah it used to run all the time.
Anyway, I replaced the VFD and the new one runs its fan continously upon power up. No change in performance occurred here.
Then I replaced the spindle and we're back up and running at full power.
New spindle noticeably quieter without load. From everything I've read and experienced in the past, failed bearings would be extremely obvious. This wasn't the case here (spindle ran fine at any RPM and relatively quiet without load)
Perhaps the windings are shot. Or some kind of short happening inside the old spindle? I notice that the new spindle passes coolant MUCH easier.
Anyway, I'm back up and running. If anyone wants to suggest troubleshooting the old spindle, I'm open to it. I.e. could it still be bearing related despite a lack of horrid noise?
For anyone reading this just trying to get back to a state of normal cutting, I recommend just buying a new kit. For $500 it's worth just replacing and holding onto your questionable parts as emergency backups.
If the Parameters are not set correct for these high speed spindles, over time the spindle motor will loose it's normal performance and eventually fail, they can easily over heat internally and you will not even know it is happening with these water cooled spindles, Parameters are key and Grounding for a long spindle life
Re: Hua Jiang/Huanyang + VFD Combo - Sudden loss of torque
Quote:
Originally Posted by
mactec54
If the Parameters are not set correct for these high speed spindles, over time the spindle motor will loose it's normal performance and eventually fail, they can easily over heat internally and you will not even know it is happening with these water cooled spindles, Parameters are key and Grounding for a long spindle life
Thanks, Mactec54
As far as I can tell the parameters were all set correctly by the previous owner.
As for the grounding, the old spindle was a 3-wire connection (no ground). The previous owner ran the VFD earth cable to our z-axis mounting plate but with nothing available at the spindle, it was not grounded. Being 3+ years old, it's possible that the lack of a proper ground contributed to the eventual failing...The newer versions of these spindles seem to have come a long way to meet proper NA electrical codes.
Without changing the entire cabling setup I basically ran a single shielded wire from the 4th pin (ground) on the new spindle back to the z-axis plate ground point - thereby completing the ground to the spindle body. This spindle already had its 4th pin connected internally to its body - but I appreciate your previous posts detailing this process if necessary!
I believe I've done this correctly, machine has been operational for 20+ hours now, but would love to know others' opinions.
Re: Hua Jiang/Huanyang + VFD Combo - Sudden loss of torque
Quote:
Originally Posted by
jwhil
Thanks, Mactec54
As far as I can tell the parameters were all set correctly by the previous owner.
As for the grounding, the old spindle was a 3-wire connection (no ground). The previous owner ran the VFD earth cable to our z-axis mounting plate but with nothing available at the spindle, it was not grounded. Being 3+ years old, it's possible that the lack of a proper ground contributed to the eventual failing...The newer versions of these spindles seem to have come a long way to meet proper NA electrical codes.
Without changing the entire cabling setup I basically ran a single shielded wire from the 4th pin (ground) on the new spindle back to the z-axis plate ground point - thereby completing the ground to the spindle body. This spindle already had its 4th pin connected internally to its body - but I appreciate your previous posts detailing this process if necessary!
I believe I've done this correctly, machine has been operational for 20+ hours now, but would love to know others' opinions.
The 3 wire spindle should not be used anywhere in the world other than China, if people did not buy them they would not be in market place, for unaware buyers, they are not to any electrical code any where in the world for a 3Ph motor use
The spindle 4th pin Ground wire should be inside the shielded cable and terminate at the VFD Drive Ground along with the input power Ground, this is very basic and the only way it should be done
Don't go by what someone else set for Parameters even if they are correct, you need to no what has been set and make a list of them
