Inverter Problems

[mikemill]

Hi
I am converting older cnc lathe to modern control, and have both axis working ok, but can't get the spindle to turn under contol.

I am useing a Mitsubishi FR-U120s VFD or inverter and have the manual. The spindle turns from VFD keypad, so on correct perameter, I get +10v on the board output when pushing spindle button on Mach, so control pulse is getting through. Spindle setup on Mach config checked and played with active low's but no joy.

Anybody got some ideas of somthing I have missed, or has experiance with this VFD.

Thanks
Mike

[Alekoy]

Hi.
Don't have experience with the spesific VFD you have, but have good experience on VFD's in general.

Have you set the VFD to remote operation?
and have you set what input on the VFD does what?
i.e.
digital input 1 - Start CW
digital input 2 - Start CCW
digital input 3 - Emergency stop (with switch wired in NC)

[mikemill]

Hi Alekoy
I have set the VFD peramiters as per manual, would it help if I emailed you the manual in a pdf, you might see somthing I have missed.

Thanks
Mike

[Alekoy]

Yes, you can do that. Mail: Alekoy -AT- home -dot- no replace with @ and .

[Alekoy]

I downloaded the manual...
You have wired up the start button between terminal SD and STF for forward rotation, (and SD to STR for reverse if you are using it) ?

if so, than you must enter the programming menu (guess you allready know how) and go to parameter "P79" and press "SET" if the display now says "1" than change it to "2" and press "SET" again

if this dosent help, try to set parameter "P75" to "0" istead of "14"

and if it still dosent work, tell me so, and I will think more about it.

[Alekoy]

double posted..

[mikemill]

Alekoy
Yes have tried 79 1-4 and tried 75-0 they all work from VFD keypad, but not from Mach

Let me confirm wireing, on pushing spindle button on Mach I get +10v on control board
connected to + terminal 2 - terminal 5
From relay on board, centre terminal go's to SD or common, NC to STF, NO to STR

If this is ok spindle should turn!

Thanks

Mike

[Alekoy]

try to disconnect the wires on STF and STR, and try with a jumper between SD and STF, with spindle speed turned up, and see if it starts now.
if it still won't budge, measure if you have any voltage input between 2 and 5
if it does move, than you will probably need two relays on the controller, one for foreward, and one for reverse, or a switch in series with the wire to SD (common)

I don't find any other settings than P79 (shoud be set at "2") that can stop it from being started, if it is a u120s-ER you have, that is.. the other models have some more parameters that can be set.

[mikemill]

Alekoy
Tried jumping SD and STR also SD and STF but no joy, although SD and STF stops spindle from turning on keyboard! Yes I have +10v across 2 and 5, also +24v across SD and STF, parameter set 79-2

Model No FR-U120S-NO.4K-EC

Thats whats annoying all the voltages are correct, it must be a setting?
Thanks
Mike

[Alekoy]

Typical..

when a VFD starts to mess with you this way, the best thing to do is to go to "Clr" and start from scratch. (reset all parameters)

and set the settings.
the ones that actually is needed is:
1: Upper limit frequency: not good for the motor over 65-70Hz, looses torque

2: Lower limit frequency: not lower than 15-20Hz, due to cooling (if you have a separate fan, you can push it to 5-10Hz depending on the noise the motor makes)

9: Electronic thermal relay: Amp-rating of your motor

21,22: bias and gain for the 0-10v signal (not needed for testing, i guess)

79: Operation mode selection: Set to "2" - external control

I actually love the simplicity if this VFD, but that dos not help when it won't do what it is told to do..

[mikemill]

Alekoy
Have been away for a couple of days.
Taking your advise I cleared the VFD settings, then tried to re programme the beast, but haveing real prpblems, can't get the 'F' for frequncey to display, have the manual in one hand and get P-0 go to P-1 set, dial in 65 and set, do I have to have F displaying before I set the number, or after, and how do you get the 'F'?
Can you advise
Thanks

Mike

[Alekoy]

Hi Mike, sorry for me being so slow with my answer, been tied up in other projects.

well, I don't really understand,
but if I understand you right, you can set the frequency in P1 and P2, but the "F" does not show?
from what I can see in the manual (not having hands on experience with this VFD, mostly programmed Telemecanique, Danfoss and similar drives)
The manual says nothing about an "F", can you remember if the "F" was there the last time you programmed?