[coils]

I did search the web, this section and the rest of the forum, but I can't find an answer to this. And I'm not an electronics guy, so please keep it simple.

I got an Emerson Control Techniques Commander SKB1100075 VFD (not hooked up at all yet) that I'd like to hook up to the G540 and control it through Mach3 once I know it's functioning properly using the keypad on the VFD.

But here's the part I am having trouble with, it's the wire(s) hookup from the G540 to the VFD because they are marked different on both units.
The G540 manual shows terminals #7 = Ground, #8 = Output, #9 = +10VDC are for the VFD.
The VFD terminals (I think I'm looking at the right ones) are T1 = 0V, T2 = Remote Current Speed Input, T3 = +10V Output, T4 = Local Voltage Speed Input. There's a B1 = Analog Output Motor Speed (but I think this is for a read out, tachometer), everything else on the B strip is Digital or 24V, so I don't know if I need any of the B terminals for this?

The only one that looks right is #9 goes to T3, since they are both marked +10V.
Does #8 = Output go to T1 = 0V?
And what about #7 (ground), does that actually go to a ground terminal on the VFD or to one of the T terminals, and which one?

Any help would be appreciated

[Eldon_Joh]

try reading this, let me know if it works

G540 VFD

[coils]

Thanks for posting that, but it didn't really help.
To me it just let me know that I'm on the right track about #8=VFD OUT goes to T1=0V and #9=+10VDC goes to T3=10V. I'm still have no idea about #7=VFD GND?
The manual for the VFD doesn't explain things to well and it's setup for multiple models.

[Eldon_Joh]

do you understand that the VFD has a ground terminal, another terminal outputs 10 or 5 volts, and you connect a pot between the two to deliver 0 to 5 or 10 volts into a third terminal for speed control?

all three wires connect into the G540, it then converts the pwm output from pin 14 into a voltage that varies from 10 or 5 volts (whatever the vfd output) to zero. it should be pretty linear. 0% pwm is 0 volts, 99% pwm is 10 or 5 volts.

you should have three wires connecting between the two.

The G540 manual shows terminals #7 = Ground, #8 = Output, #9 = +10VDC are for the VFD.
The VFD terminals (I think I'm looking at the right ones) are T1 = 0V, T2 = Remote Current Speed Input, T3 = +10V Output,

should be connected a wire from
T1 to #7
T2 to #8
T3 to #9

if you get #7 and #9 backwards, i suspect the G540 has a diode across the two terminals, and this will effectively short the VFD ten volt output to its ground.
the vfd should tell you if that happened, it should not blow the vfd up.

[coils]

As mentioned I'm not an electronics person, and I don't want to fry anything, to me having to pay another $250-500 for electronic(s) because of a wire being hooked up wrong is just stupid.

do you understand that the VFD has a ground terminal,

I understand what an electric ground is, but the only thing marked as ground is 3 screws for the "line in" & "motor ground" at the bottom of the VFD where all the higher voltage action happens.
About half way up are the "control terminals" and none of those are marked as ground (on the drive itself or in the book).
That's why I'm mainly questioning the ground hookup, I couldn't understand if it was a Physical Earth ground (PE) or if it was some electronics special ground that used a different symbol other then a "-" (negative symbol).
See I told you I know very little about electronics

another terminal outputs 10 or 5 volts, and you connect a pot between the two to deliver 0 to 5 or 10 volts into a third terminal for speed control?

Now that confuses me too, I'm guessing the "pot" is a potentiometer (a knob you turn to adjust voltage, like a volume on a radio), but I thought that was built into Mach3 and electronically adjusted the voltage (or sends a signal to adjust it) through the pin which goes to these terminals on the G540 which tells the VFD what it should do?

if you get #7 and #9 backwards, i suspect the G540 has a diode across the two terminals, and this will effectively short the VFD ten volt output to its ground.
the vfd should tell you if that happened, it should not blow the vfd up.

The following is from the G540 manual, and this is why I'm worried about hooking something up wrong.

Do not short VFD OUT to any other terminal. Do not reverse polarity to VFD GND and VFD +10V or the G540 may be damaged.

Thank you very much for trying to help me with this, I am going to look this all over and scratch my head some more before I do anything LOL

But what really sucks, there's really no info on the net for these other than the manufacturer's manuals. I've tried searching as many ways as I can think of and all that comes up is the manufacturer's site and places selling them which link you back to the manufacturer. So it's like running in circles, using up a lot of time and I'm still in the same place I started.

[coils]

And to add more to my confusion, I just noticed today (Saturday) that this VFD can also be controlled by a RJ45 connection and use Modbus RTU, so I looked into this too a little and it just seems to simple to be true to me, but I know I'm missing something about hooking it up this way and will need to spend more time looking at this later on.

[Eldon_Joh]

no, the g 540 does not output a voltage.
it outputs a voltage proportional to the voltage delivered to it by the vfd.

this is why you need three wires connecting the two of them!


the 10 volt output relative to its ground terminal, may or may not be electrically different than the other ground terminals offered by the VFD for other switches.

it is safe to connect that ground to the electrical ground, provided you don't do something stupid.
a typical vfd has several isolated power supplies to solve this problem

[zer0fighter]

I am running a G540 to a Hitachi VFD. There are 3 wires from the G540 that you need. The VFD 10V DC +, the Ground, and the VFD V+ Output signal. This part is relatively straight forward, the tricky part for me was getting the base setup of the VFD just so it would spin my motor. I can take specific pictures for you if it helps, but sine my VFD is different, it might not.

[Al_The_Man]

I understand what an electric ground is, but the only thing marked as ground is 3 screws for the "line in" & "motor ground" at the bottom of the VFD where all the higher voltage action happens.
About half way up are the "control terminals" and none of those are marked as ground (on the drive itself or in the book).
That's why I'm mainly questioning the ground hookup, I couldn't understand if it was a Physical Earth ground (PE) or if it was some electronics special ground that used a different symbol other then a "-" (negative symbol).
See I told you I know very little about electronics


Now that confuses me too, I'm guessing the "pot" is a potentiometer (a knob you turn to adjust voltage, like a volume on a radio), but I thought that was built into Mach3 and electronically adjusted the voltage (or sends a signal to adjust it) through the pin which goes to these terminals on the G540 which tells the VFD what it should do?

And to add to your confusion, unfortunately the term Ground and the earth ground symbol has become misused to the point it is meaningless, especially in N.A. where the term for power common (ground) is also used for earth ground, as opposed to UK for e.g. where one is ground the other earth.
Here the Earth Ground symbol is often used for any P.S. common regardless of whether earth grounded or not.
Even one of the books quoted as being the Electronic Bible, 'The Art Of Electronics' uses the earth ground symbol throughout the book and does not even give any definition of such symbols.
Modbus is a very good way to control your VFD if you can configure your particular VFD, I am not sure whether there is a Mach generic pre-written Modbus plug-in apart from the one for the Huanyang VFD from China.

Al.

[coils]

provided you don't do something stupid.

That's what I'm worried about




zer0fighter if you still have the manual just see what they are calling those terminals you hooked up to would be good enough, maybe the two companies use common names / description for the terminals and I can use that as a reference too.



LOL Al that's a funny pic
I know the Modbus thing will be hard to get running, but I want to look into it later because it sounds like it might have better features & functions.




But back on the topic of this thread.
I found a pdf that explains the control terminals better then the manual, I'll try to post that one page and I'm hoping it will give more info for you guys to help me.

[Eldon_Joh]

t1 is ground, it goes to g540 #7
t3 is 10 volt output, it goes to g540 # 9

g540 #8 goes to vfd t4 which is a 0-10 volt input.

[coils]

Thanks Eldon

You know I was looking at that pic and the pins for the G540 in the manual right after I posted it, and after about 10 minutes I came to the same thing you just posted. You know the light bulb came on type of thing
Just having those few extra words it makes so much more sense.
The +10V T3 explains itself.
And T1 "common" can be thought of as a ground, even though it still has that 0V next to it (this is still dumb to me), made me think a little about it though.
Then I was looking at T2 & T4 for the last connection, well the notes column made that easy to figure out with the "0 to +10VDC" comment, it's an "input" to the VFD but your sending an "output" from the G540 (#8 VDF OUTPUT) and T4 falls into that voltage range.

See just a few extra words makes it all fall into place, even for a dumbass like me. LOL


For now, thank you to everyone, I'll keep this thread going as long as I'm working on this part of the adventure. Hopefully I'll get time over the next couple days to mess with this more.

[zer0fighter]

coils, sounds like you got the answer you need.

Have you been able to get the VFD to run the motor without the G540 connected? For me that was tougher, the Hitachi manual is pretty complicated for someone who doesn't do electrical installs for a living. I'm pretty good with tech in general, but I find electrical documentation tough to follow as different symbols and words are used by different companies. No consistency.

[coils]

Yeah I hope I got it figured out


No I didn't get the VFD hooked up to the motor yet, I was planning to do that today (Sunday), but life got in the way. I should have enough time Monday to get the power lines hooked up.
I think doing the basic "setting it up" will be kind of easy, the company has the 10 main parameters used on the front label and you don't need all those to get a motor turning, there's also a video on youtube showing this basic stuff too.
Now learning how to do more with it will most likely be a challenge in itself

I'll also have to look on here and youtube for setting up Mach, I seen it before and it seems do-able to me, just got to pay attention and make sure I double & triple check every step as I go.

[coils]

Well I didn't get to finish doing the AC lines on Monday like I thought I would, but did get them finished Tuesday, using the buttons on the VFD I could control the motor. So that was one step in the right direction.

Thursday night I had a little time so I hooked up the wires from the G540 to the VFD, but it didn't work, so I got to check on the Mach3 setup again and see if I missed something in there. When I hit the "spindle" button on the screen or type in M3 in the command line it shows something like "PMW minimum" something, sorry didn't right it down and forgot it already.

So I'll have to mess with it some more this weekend to see what I screwed up, and if I can't figure it out or I'll be asking for more help

[fishin_fl]

Coils..
I have gotten the RS232 to RS485 working via modbus. I also have gotten it working via TCP modbus. I am connecting through Mach3 but not to a G540. I am basically sending Control words in binary from mach3 to the Emerson Drive. Via parameter 641 for control word and 120 for preset speed. I have not tried connecting the 0-10 vdc pot yet.I have started taking snap shots of the VFD parameters and the way I have the brain setup in MAch3.

Do remember that if modbus is the way you want to connected it either serial or tcp you will need one more device for each setup. First a RS232 to Rs485 converter. I am using a B&B Elctronics isolated converter. Model: 485LDRC9. Second setup you would need the SM-ethernet module card.

If you do not want to use modbus there is another way....

You could use an opto isolator and use the TTL 5v triggers from breakout board to activate relays on the opto isolator. DC Opto-Isolated Output Board

This two would need parts. An additional power supply for output relays, and wiring.

So far that is what I got. Emerson Controls have a great drive. This SK VFD is just like their SP Drive just in a small foot print. This drive can seem to be very complicated but after awhile things get moving.

Ill check back in with more literature of my setup this weekend.

Brooks

[coils]

Hello Brooks
Thanks for the info, but most of it went right over my head
I think I would like to look into Modbus more in the very near future, but I need to look into it more first, since I'm having this much trouble with this three wire hook up. LOL




I got to mess with it for a while Friday night, I made progress but it's still not working and I don't know if it's something in Mach3 or the VFD, but I'm thinking it's the VFD.
Here's what I was messing with.
First I was just double checking things in the ports & pins area under all the tabs to see if I could notice anything, and trying to figure out what some of them were. But I noticed in the Motor Outputs area on the Spindle line it only had a number in the Step Pin# column, all the others where 0 (zero). Well I didn't think that was right so I came back upstairs (mill is in the basement) to look at the Mach3 & G540 manuals.
And I guessed this one, but I put a 1 in the Step Port column (more on this later), I figured it needed this since everything else needs a Port #. Still nothing, so for about the next hour I was putting numbers in the different columns to no avail. By now I was starting to get a little frustrated and was about to call it a night.
I used the Gecko G540BVFD xml when I set this machine up, and it looks like Gecko got the Step Port column wrong with the 0, I think it should be 1 (or whatever port your using). Hope this is right and helps someone later.

So now is the part everyone that wants to help has to pay attention to.
I got out the multi meter (an automotive one, nothing fancy) and I set it on 20VDC, I checked the three terminals on both the VFD and the G540. I put the negative lead on the GRD-0V-Common terminals and check the other two terminals for power, I was getting a constant 10.2V on the +10V and nothing on the OUTPUT/INPUT.
Then I set the spindle speed in Mach3 to 1000rpm (oh I have my spindle set to 10Krpm max) and I did the same test on both, still had 10.2V on the +10v, but now I had .95v on the OUTPUT/INPUT. So I did a few more tests and got these numbers; 2.96v at 3k rpm, 4.94v at 5k rpm, and 9.8v at 10k rpm. Did the same going backwards and got the same numbers.
But the spindle motor will not power up.

I don't know if I'm missing something in Mach3 or the VFD? Anyone got any ideas where to look?
Oh got to ask, In Mach3 Ports & Pins under Spindle Setup; How do I know what to set PWMBase Freq to( I have it at 5 since that's in the Mach manual), and what about Minimum PWM ( I have it at 0 )?
I'll have to look at the VFD manual and scratch my head with that some more.

[coils]

Well I got it so I can turn the spindle on & off from the Mach screen, it comes on at full speed and stays there, no speed control at all.
So for now I'm done wasting my time on this, I got other things that need to get done.

[zer0fighter]

Coils, that's good news, I think the rest of your setup is software now. I just ordered a handheld tachometer from eBay to calibrate my spindle speeds, hopefully that is a fruitful endeavor.

Sent from my SAMSUNG-SM-G900A using Tapatalk

[coils]

Well hopefully someone can answer this.

Last night I had some free time to mess with mill a little and did a few cuts on some wood to check it's moving the distances it should, you know just playing around.

The last thing I did was that "road runner" thing that comes with Mach, and it automatically set the speed of the spindle to 60, and the VFD was running at less then 60hz. So I reset the speed in Mach to 80 and it changed the speed, so messing with that I found setting the speed to 105 it would set the VFD to 60hz. I also checked the voltage on the INPUT/OUTPUT terminal and it was changing as I changed the speeds from 30 - 105 getting a max voltage of 9.98.

So why am I getting a voltage change putting in these small numbers rather then rpm? It's like it's only accepting voltage percentages, like 60 is 60% and so on, rather then letting me put in rpms.