Starting from scratch (again) - Next Step - VFD

OK, steppers at least partially functioning for now, onto the next step

Existing VFD is a Minarik VFD05-D230-PCM connected to 220v 1ph running a 230v 3ph motor
Existing mach3 setup is 0-10v control (through the C11G BOB via mach it's set to step/dir)
I never got the motor reversal to work properly and had to fake it using m8/m9 to control a relay on the BOB to get teh VFD to reverse, hopefully that's something I can fix now withe linuxcnc and the 7i76

VFD wiring has the following - Voltage following 0-10v


D S3 S2 S1 E1 E2

S3 is not used right now but it's one end of the pot with the other being S1 and the wiper would be S2
S2 and S1 are the GND and 0-10v signal lines

D is the enabled and is connected to E1 via relay on the C11G and controlled by the M3 command
E2 is the direction and is either shorted or open to E1 to change the direction of the motor

(Does seems odd that the D terminal is for Enabled and the E2 terminal is for the Direction but that's what it shows....)

Anyway, apparently that's the Asian way of doing things so I'll need M3 to close the enabled AND close the dir pins and then M4 to close the enabled while opening the dir pin.

Looking at the 7i76 TB4 pins 1,2 and 3 it says that spindle + is one end of the pot, spindle - would be the other and spindle out would be the wiper Good enough I can wire that to S1,3 and 2 respectively

Then it gives me enabled (p6) and dir (pin8) as isolate opto switches so hopefully I can use those to control the two separate switches I need via M3 and M4

Anyway, on the PNCconf under TB4 I only have POT output and POT enabled (under the 0)

1.. Does that just turn everything for the spindle on TB4 on automatically?
2.. It's talking about what happens when +5/-5v is supplied to TB4, do I supply the 10v separately to the card (separate from field power?) I have +/- 5v and +/- 12v available in the cabinet, never thought about needing a separate 10v source
3.. What's the best approach to dealing with the enable and dir switching (VFD wants them connected or open to E1) do they need to go to a separate set of relays then I guess

Thanks for the sanity check

M

Typically the VFD provides the 10V for the 7I76's potentiometer simulator

Since the direction and enable inputs work as contact closures
(the contacts should be replaceable by the 7I76's optos)
no other power supply should be needed

The enable and direction signal polarity are not clear but can be determined
with a voltmeter

Makes sense then, the 7i76 is truly acting as a pot replacement then. I'll test the enabled - dir switch tomorrow.

OK, spindle control seems (according to meter and test lights) seems to working and looks to be reversing correctly
I'll have to deal with tuning later

Next step will be the spindle encoder, looks like I'll have to make a different setup than the one currently on the machine though.
Thanks again, stay tuned for a new encoder thread
M

Found an old US digital encoder, 5v A B with no index, 1000 lines. I might be able to make this fit somewhere with a pulley to the spindle (maybe)

Hooked to TB3 as per the 7i76 manual (pins 7=A+, 9=GND,10=B+ and 12=5v)

As far as I can tell the only setting in pncconf is on conn3 (I'm still really confused with navigating around the pncconf vs pins on the 7i76)
Now, is there a way to test this encoder without having the actual VFD hooked up and the encoder connected to the spindle?
As in can I spin the encoder by hand and see a resulting ??? on the screen?

Also, for threading, can I use a separate single pulse, currently the spindle has a single slot / optical sensor that mach3 was using, I'm thinking that could be wired into pin 13 IDX+ on it's own

M

mooser wrote:

Found an old US digital encoder, 5v A B with no index, 1000 lines. I might be able to make this fit somewhere with a pulley to the spindle (maybe)

Hooked to TB3 as per the 7i76 manual (pins 7=A+, 9=GND,10=B+ and 12=5v)

As far as I can tell the only setting in pncconf is on conn3 (I'm still really confused with navigating around the pncconf vs pins on the 7i76)
Now, is there a way to test this encoder without having the actual VFD hooked up and the encoder connected to the spindle?
As in can I spin the encoder by hand and see a resulting ??? on the screen?

Also, for threading, can I use a separate single pulse, currently the spindle has a single slot / optical sensor that mach3 was using, I'm thinking that could be wired into pin 13 IDX+ on it's own

M

You can test the encoder by connecting it and watching the encoder position (via the watch window or halmeter)
as you turn the encoder shaft

Note that since you have a single ended encoder you will have to jumper the 7I76 encoder inputs for single ended = TTL mode

You can use an independent index source so the slot detector should work OK

OK, encoder does something (at least there's numbers on the screen in location and velocity, nothing on the "scope" so at least it's working. I'll have to see about gearing it to the spindle somehow but if I can it should be better than making my own 100 count disc

Now somehow I screwed up my other settings and I've got a new error stopping Lcnc from loading, Getting pretty good at finding those now at least

Thanks again
M

OK, semi success (well not really but no smoke so I've got that going for me...)

I've got axis movement, e-stop and limit switches working (x-axis limit is just hanging off the end of the machine but that's another story)

Spindle VFD powers up so the contactors etc are working but there's something wrong with my wiring on the 7i76 > VFD

Are the Opto switches supposed to be connecting ENA+ and ENA- and then DIR+ and Dir- or are they connecting the appropriate ones to the spindle signal (ie spindle - to ENA + type of thing?

When I turn the spindle on the enabled light on the VFD isn't lighting up

If I short E1 and E2 from the VFD it lights up and the motor tries to turn very slowly
*** I doubt I have the settings for the VFD in LinuxCNC so the speed of the motor is going to be out to lunch ***

Looking at some wire sample diagrams and they have the spindle + (10v I guess) connected to pins 3, 6 and 8 (spindle +, enabled + and direction +) but I think I only need the spindle + connection

but it's not clear (to me) in the manual what connection is being made on the enabled or direction on the 7i76 and I since they are opto I can't test without it being powered up (trying to keep the smoke inside for now)

Right now I think I need to connect my E1 pin to both ENA- and DIR- and then my enabled (E2) to ENA+ and dir (D) to DIR+
(or maybe vice-verse depending on the polarity of the VFD)

Does any of this make sense?
Thanks
M

Just tried E1 and E2 to pins 5 and 6 (ENA+ and ENA- and the enabled light turns on but stays on regardless of if the spindle is commanded on or off in Lcnc so back to the manual for more reading.
(plus I checked the output on the spindle and it's only like .5v regardless of the speed commanded so something's really out on my setup/wiring)
M

if the VFD stays on regardless of LinuxCNCs spindle enable state,
this suggests the you have the ENA+ and ENA- swapped
(wrong polarity)