Anyone use an Invertek VFD with a 7i76e? I'm not getting a response... still.

Hi all,

I hope you're all well in these pre-Christmas, present Covid, and hopefully post lock down times.

My electronics enclosure showed first signs of life the other day, with all stepper motors responding to the 7i76e and LinuxCNC. With that done, I've moved onto connecting my VFD to the controller using the usual analogue TB4 interface.. but I'm not having much luck. Nothing comes up with an error, but nothing happens either.

There are tons of walk-throughs and "quick start" guides for Huanyang and other brands of drives, but Invertek seems to be relatively obscure. So since I'm alone in a shed, somewhat cross-eyed from looking through the wiring, the VFD parameters, PNCConf, documentation and my multi meter, if anyone can offer some insight into what I can try next, I'd really appreciate it. I just can't seem to find what I'm missing.

I can't attach the manual to my VFD due to file size limits, but I'll try to provide as much info here as possible. However, if you'd like, here's a link to the VFD manual:
isource.invertekdrives.com/client-upload...ide%20A5%20V1.07.pdf

Firstly, the wiring.

The VFD control terminal has the following arrangement: (Due to parameter 15)
Pin 1: 24V DC
Pin 2: Digital Input 1 (Start/Stop) (links to pin 1 to complete circuit) 0V = STOP, 24V = RUN
Pin 3: Digital Input 2 (FWD/REV) (also links to pin 1 to complete circuit) 0V = FWD, 24V = REV
Pin 4: Digital Input 3 (Not connected at present, but would also link to pin 1 if used)
Pin 5: 10V (Reference voltage for potentiometer)
Pin 6: Analogue In 1 (wiper of the potentiometer/speed control voltage)
Pin 7: Analogue ground for the potentiometer.

MESA 7i76e Pinout for TB4 (just to keep it fresh in your mind, I know many of you will know this):
Pin 1: Ground (Pins 1-3 combined simulate a potentiometer for speed control)
Pin 2: Analogue Speed out (0-10V)
Pin 3: 10V Reference Voltage
Pin 4: Not connected
Pin 5: Spindle Enable -
Pin 6: Spindle Enable +
Pin 7: Spindle Dir -
Pin 8: Spindle Dir +

So the Pins (From the Mesa 7i76E perspective) are wired as such to the VFD:
MESA                                                                                       VFD
Pin 1: Ground                                                  wired to            Pin 7: Ground (Pins 5-7 are the analogue speed control pins)
Pin 2: Analogue speed voltage (wiper)           wired to            Pin 6: Analogue In 1
Pin 3: 10V Reference voltage                         wired to            Pin 5: 10V Reference Voltage
Pin 4: Not used                                          NOT WIRED          Pin 4: Not used
Pin 5: Spindle Enable -                                   wired to             Pin 2: Digital Input 1 (Stop = 0V, Start = 24V)
Pin 6: Spindle Enable  +                                 wired to             Pin 1: 24V DC
Pin 7: Spindle Dir -                                         wired to              Pin 3: Digital input 2 (FWD = 0V, REV=24V)
Pin 8: Spindle Dir +                                        wired to              Pin 1: 24V DC

All wires are sound and have confirmed continuity. The Mesa's output (relative speed voltage) moves from 0-10V as expected. This is even measured on the VFD terminals. Yet the VFD simply continues to say "STOP" which is the default state.

Next thought: VFD Parameters:

Now it should be noted that this VFD works perfectly from the keypad when operating that way. However, for electrical safety... I'd prefer to control the VFD/spindle via the controller. All the parameters from 1-11 (mostly pertaining to motor settings) are correct and seem to work well... or at least, I haven't found any problems yet.

P12:
I've set parameter 12 to respond to the control terminal (setting 0) but no response has been seen either on the readout or spindle movement.

P13: (General purpose "industrial", fan or pump mode)
Set to industrial (general purpose)

P15: (This sets the control digital and analogue inputs as described above)
Set to 0, this forms the basis of the wiring setup above.

P16: (Analogue Signal format)
Set to U for unidirectional 0-10V (Since Digital input 2 handles the direction, the analogue voltage should be unidirectional for speed).

Next thought: PNCConf
I went through PNCConf, and did not enable the Axes-based Spindle, but made sure to enable TB4 to be an analogue spindle controller. I only have "not used", "analogue spindle" and "custom signals" as options. So I chose the "analogue spindle" option. This seem to send the right voltages, but I still can't get a response from the VFD. 

If there's anything I can try, something you see that might be wrong, please let me know.

Thanks for taking the time to read this. It's ok if you can't help, I'm a newbie and am not confident about offering what little wisdom I may have.

Take care out there!
Hamish.

Did you double check the function of enable and direction?

If you select unidirectional mode (assume this means it will never run in reverse) and then use the direction pins does that cause a conflict?

Hi Michael,

Thanks for getting back to me. I have tried your suggestion to switch parameter 16 (Analogue signal type) to bi-directional input, but I'm afraid I'm still getting no response from the VFD.

I'm sure I'm missing something, but I'm somewhat stumped at the moment.

Anyway, I really appreciate your help!
Hamish.

Hi everyone,

Success! The VFD and spindle are responding. The wiring was correct, and the parameters on the VFD were ok.

I'll double check the parameters later and list them here, but this thing has be driving me nuts for days, so

However, restarting PNCConf and creating a new config from scratch (rather than modifying an existing configuration), and going through each page in excruciatingly slow and steady way seemed to do the trick.

At some point I'll see if I can find out which setting was different in my other LinuxCNC config to cause these issues.

Thanks all, and I'll try to upload what I've learned here for those that follow... and may find themselves in a similar situation.

I probably won't be around for the next few days... so merry Xmas everyone.
Hamish.