800w spindle - noise & controlling remotely

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Originally Posted by HankMcSpank

I did some speed research earlier...my interpretation may be incorrect, but I thought these VFDs put out a PWM pulse stream (& relies on the inductance of the spindle coils to essentially filter the VFD output pulses & restore a sine wave from them - similar to filterless class D audio amplifiers). If that the case, then the aforementioned 230V output, will be the maximum peak to peak level of the restored sine wave)

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Yes the VFD outputs a PWM signal which is subsequently filtered by the inductance of the spindle, but there's a bit more to it. The input to the VFD is the mains, which is simply rectified and stored in some capacitors - this is called the DC bus. The DC bus voltage is therefore around 230*1.414.. =325V DC, so the peak voltage of the PWM waveform outputted will be around 325VDC. That means the rms output voltage will be 325/1.414=230V AC. Other things do influence the DC-bus voltage and your drive can do more than use a simple PWM signal with vf control to change things, but that's not important right now...

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Originally Posted by HankMcSpank

I have skype, which I seldom use & I can't immediately lay my hands on my webcam - if I find it I'll give you a shout on here :-) (but missus has furrowed brow which roughly translates into "you must not pursue this anymore this evening!")

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Don't need a webcam.

Just measured my spindle and I've got 4.4 ohms between phases. When driven by AC or pulses the impedance seen is higher because of the inductance, so you can't just use simple ohms law to work out the current.

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Originally Posted by richie00boy

Just measured my spindle and I've got 4.4 ohms between phases. When driven by AC or pulses the impedance seen is higher because of the inductance, so you can't just use simple ohms law to work out the current.

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Thanks for that ...I'm measuring 3.5 ohms between all phases. (it was late & I'd been onto this all day...& with the benefit of a good nights kip, I now fully realise that my head was fogged!)

I guess my quickest way forward here is to buy another 800w spindle & hook that up ...if it works, then my old spindle was faulty (which I think it is), if it still trips then I can sell it on!

Some of these water cooled spindle adverts tout themselves as 'four bearing' ...do I need this if I'm only milling pcbs & acrlyic? (in other words what does four bearings bring to the party - they're about £30 more vs the cheapest 800w water cooled spindles on Ebay)

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Originally Posted by HankMcSpank

I guess my quickest way forward here is to buy another 800w spindle & hook that up ...if it works, then my old spindle was faulty (which I think it is), if it still trips then I can sell it on!

Some of these water cooled spindle adverts tout themselves as 'four bearing' ...do I need this if I'm only milling pcbs & acrlyic? (in other words what does four bearings bring to the party - they're about £30 more vs the cheapest 800w water cooled spindles on Ebay)

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I believe all are 4 bearing, forget the crap the sellers are telling.

I decided to read a bit again the manual, to check what the problem could be.

Lets troubleshoot a bit:

1. check if by error you programmed 230v 60HZ instead of 50HZ

2. check if you properly established accelaration and deccelaration time , i use 10 seconds

3. check 5.4 of the manual , setting your motor
AU2 should be set to 0 instead

As far as i remember, some motors had problems with the auto tuning, so don't use it anywhere for now

uL: Base frequency 1 (rated frequency) set to 400
uLu: Base frequency voltage 1 (rated voltage) set to 230
F405: Motor rated capacity set to 0.75
F415: Motor rated current set to 3.4
F417: Motor rated speed 1410 / I am lost why i set it like this/

4. 5.9
UL=400
LL=0.0

5. 5.11
Pt=0

make sure F416 is set to 60


In general avoid the stuff like boosting and so untill you make it work.

if you doubt a particular parameter just drop a line here, i will check and report

You did not mention what the trip says exactly?

Many thanks...I will check these parameters this evening & report back :-)

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Originally Posted by silyavski

I believe all are 4 bearing, forget the crap the sellers are telling.

1. check if by error you programmed 230v 60HZ instead of 50HZ

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No it's programmed for 50Hz.

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Originally Posted by silyavski

2. check if you properly established accelaration and deccelaration time , i use 10 seconds

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I have the same setting for ACC & DEC (10 seconds)

Quote:

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Originally Posted by silyavski

3. check 5.4 of the manual , setting your motor
AU2 should be set to 0 instead

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It was set to 0.

Quote:

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Originally Posted by silyavski

As far as i remember, some motors had problems with the auto tuning, so don't use it anywhere for now

uL: Base frequency 1 (rated frequency) set to 400
uLu: Base frequency voltage 1 (rated voltage) set to 230
F405: Motor rated capacity set to 0.75
F415: Motor rated current set to 3.4
F417: Motor rated speed 1410 / I am lost why i set it like this/

4. 5.9
UL=400
LL=0.0

5. 5.11
Pt=0

make sure F416 is set to 60

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Mine are all set to be the same as the above.

Quote:

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Originally Posted by silyavski

You did not mention what the trip says exactly?

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OL1

I'm seeing this info for the stored 'trip' info...

F 2.4 (The operation command value when the trip occurred is displayed)
C 132 (The inverter output current when the trip occurred is displayed. %/A - huh?)
Y 127 (The inverter input voltage (DC detection) when the tripoccurred is displayed. (%/V).
P 10 The inverter output voltage when the trip occurred is displayed. (%/V)
L 174 The inverter load factor (%) at the occurrence of a trip is displayed.
:o 2.4 (The inverter output frequency (Hz/free unit) at the occurrence of a trip is displayed.


...I'm not fully understanding the %/A or %/V ...nor the L 174 figure?

reasons for OL1 trip:

• The acceleration time ACC is too short. • Increase the acceleration time
• The DC braking amout is too large. • Reduce the DC braking amount and the DC braking time
• The V/F setting is improper. • Check the V/F parameter setting
• A restart signal is input to the rotating motor after a momentary stop, etc. • Use (auto-restart) and (ride-through control).
• The load is too large. • Use an inverter with a larger rating.


It should be 3 -• The V/F setting is improper

There are settings that affect other setting. Just to be sure check again
5.11 manual
Pt=0 ?

I start to wonder. Are your phases connected correctly and if there is a continuity in all of them. That crappy chinese connector could be making some bad connection for a second.
I remember now there was a time my VFD was tripping and i disassembled the whole machine. At the end it turned the crappy connector. Flex on the cable made a bad connection there. It took me 3 days / 10h per day to figure it

Ps.
check F400 if set to 0.
if not, this could be the problem.

If set to 0, read section 6.1? and try to autotune the motor, but separately from the vector control. Do not change Au2 from 0, just follow the instructions and check if trip will appear after 3 seconds, and what that trip will be.

The other cure if all this still dont work is to sit down. read the manual step by step and check everything. Cause this inverter can store various motors, can be controlled in various ways, so there could be the problem.

At the end i believe it has something to do with the vector control, faulty spindle or bad connection on phase

Because there might be something set wrong try a 'factory reset' and then put in the parameters that silyavski says.

I really do appreciate your help (Eddy I'd already done your suggestion - to no avail).

I've continuity between all phases (3.5 Ohms...which seems to be about right)...I have no shorts to ground. I've also checked from the wiring (at the VFD end) with the spindle cable plugged in at the spindle end - checking for continuity & making sure there are no shorts...I'm pretty confident it's not the wiring. I've tried a coupole of permutations of connections to the spindle (one permutation the spindle tuned the wrong way...as expected)

My gut feeling is that it's still the spindle...on account of the noise it wheezes out even when turning very slowly & the fact that the spindle casing gets fairly warm even at the very slow turning I can coax it to do before it trips.

silyavski ...I've revisit this again with your last input in mind. Re the V/F setting...I turned it down to 50V (figuring I = V/R) to see if I could get the rotation higher before it trips, but it still trips out at about 2.9Hz.

Apparently this spindle has sat around unused for a considerable length of time (but was previously used a lot without incident)...I can't see how it sitting around on a shelf would cause a VFD to trip though.

Anyway thanks once again :-) (I actually submitted a best offer on a new 800W spindle 48hrs ago which has now just expired - that would have proved one way or the other!)