1340GT lathe is now alive, thanks to this community!

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skcncx

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My lathe is finally alive...

Thanks to this community, I finally have it wired up with the VFD and some of the common options other users have integrated into theirs. I never would have been able to do it without @mksj and other reference docs posted on this form. Especially the VFD config parameters with the Hitatchi software.

Just having slow start and braking is well worth the extra effort over my initial single phase motor option.

I went a different route on wiring, entirely re-wired and using AutomationDirect P1000 series and the P1AM-100 arduino based controller for switch inputs to relay outputs to VFD. This is mostly an exercise in learning and because I wanted to.... it's not totally justified. I may add an hour meter, possibly my own version of ELS and automatic two stage braking at certain RPM.

I ran through all gear selections for 3 minutes to run it in per manual. I noticed at higher rpm there is more noticeable whine in forward than reverse. Mostly coming from the QCGB gears. I took the QCGB front panel off and was surprised how much grease I did not get out initially from below... plus the gears had over spay when they painted the machine. After quite a bit of cleaning it was noticeably quieter at higher rpm. I'm curious to see how effective the drip oiling mechanism will work.

Pics show my setup... and if I did it all over again, I'd just get one large enclosure and put everything in there... it would simplify having to route my wires externally from PLC to VFD and 24 power supply for the main logic/switch circuitry. I started with intentions to have all my wiring be super neat, really professional... but only working on this a couple hours a week, this past weekend I just had to get it up and running. If anything, I learned a LOT throughout this process.. basic circuitry, PLC stuff, panel/enclosure layout. I have a new appreciation for thought and amount of work this takes.

I used a HF US general 72" tool chest, shortened the draws on the left side to accommodate my VFD enclosure.... that was more work than worth it in the end... should have just used the entire drawer space and put a door on the front or larger cutout on the end w/door for servicing. Oh well. I at least get to keep those drawers which are only 6" deep for small stuff.

Still need to mount DRO and once in place, level/align it. For now, using it as is! There's always time to tweak my setup.

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That is really awesome @skcncx. Thanks for sharing your experience.
It is my desire to someday become more knowledgeable in the electronics aspect of my machines and incorporate some of that into my 1440.
 
7milesup said:
That is really awesome @skcncx. Thanks for sharing your experience.
It is my desire to someday become more knowledgeable in the electronics aspect of my machines and incorporate some of that into my 1440.
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Thanks. I still have lots to learn... this was a perfect opportunity to combine my software knowledge with electronics. It was simple enough but also had enough complexity for a first project. Can't say I know what I'm doing, but I have at least put together something that works. My e-stop is both software AND hard wired in case the PLC goes to lunch. How much I use the proximity sensor for threading, jogging in forward or reverse and 2 stage braking will be determined as I use it.
 
I had a 8" Pratt Burnerd set right 3-jaw chuck on my 1340 and did a lot of 40 tpi threading both OD and blind hole. Mark did the wiring and electrical for the VFD and the proximity sensor, which I used a lot. The soft start function and two stage braking really helped reduce wear and tear on my lathe.
 
skcncx said:
I went a different route on wiring, entirely re-wired and using AutomationDirect P1000 series and the P1AM-100 arduino based controller for switch inputs to relay outputs to VFD.
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What are you doing with the PLC and the Arduino?

Roger L
 
Here are a couple of things I see with your photo. The area marked in red will have oil dripping from it and will need some sort of drip can. The area marked in green I think you should have a chip pan installed, maybe you already have something in mind. I think you should install the original drip pan, you will be surprised at how much oil and chips stack up in there.

Other then that it looks great!
 
rogerl said:
What are you doing with the PLC and the Arduino?

Roger L
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I'm taking the input switch signals and converting them to output 24v signals to the VFD's logical inputs. The PLC is a proxy between physical switches on the lathe and VFD motor commands. It's very simple and overkill in the sense that you absolutely do not need plc/software to do this. The software is taking responsibility for what you would normally have to do via more complex wiring circuitry.

The long winded version below...

I have several switch inputs for the various functions... run forward, run reverse, jog forward, jog reverse, 2 stage brake, proximity sensor, belt cover panel, e-stop signal, etc.. The PLC software reads the inputs (HIGH/LOW digital inputs) of the switches and sends the 24v signal to the VFD's logical inputs. The VFD's inputs control the motor operation assigned to the given inputs. If the run forward switch (it's just a limit switch on the lathe) is switched on, the PLC via a solid state relay will send a 24v signal to the logic input 1 on the VFD which is the run forward command. For jog forward, you would send 24v signal to logical input 1 and 3. 1 for run forward, 3 for running it at the jog frequency configured, in my case 10Hz.

My e-stop is basically two switches, one NC and one NO. This way, the PLC software knows if it's pressed and can act accordingly... but as a backup, it also physically controls all/any 24v signal to the VFD in case the PLC software is borked and not able to respond... which would mean, e-stop wouldn't work and very unsafe. So having a physical backup is critical.

The software is written like a state machine. Basically, you can only enter and exit certain states from valid states. The 3 main states are idle/neutral, running and fault. You cannot go from a fault state to running. For instance, it will only activate the VFD inputs for running if it's from an idle state where the belt panel is on and e-stop is not activated and no other run switches are activated, except one. Any time it recognizes a faulty state, all VFD signal commands are turned off and blinks a red fault light.

If I were to put the run lever on the carriage to it's run forward position and then while running activate the jog reverse switch, those are incompatible run operations the PLC stops motor and you just entered into a faulty state. Running or jogging can only ever happen if it was from an idle state. If two run commands are on, the PLC requires all run commands to return to their idle/neutral position before it will run again. This also provides safety when pressing the e-stop. If you activate e-stop you are likely going to have the run lever still activated. If you forget to return it to the neutral/stopped position, you don't want the lathe to turn when you de-activate the e-stop if you forget to return the run lever to it's neutral position before de-activating the e-stop. So you de-activate the e-stop, you are still in a faulty state until you return all run switches to their neutral/idle state. You then exit the faulty state and can return to normal run/jog operations.

Being a bit pedantic, PLC is loosely used as I'm not sure Arduino systems are considered to be PLC in the traditional sense. All my software is c++/arduino based, not ladder logic. Automation direct just wrapped their P1AM-100 controller around an arduino board and made it possible to control their input/output components via traditional 24vdc signals but programmed like an arduino. The same P1000 series platform from automation direct also has more traditional PLC and ladder logic controllers. I just chose the arduino version because it's what I know.

On the surface, it's very simple software logic but you can also end up in awkward states if not done correctly, so testing is key. I think in total I have around 200 lines of code, much of it is just pin configuration and static values.
 
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Just for fun said:
Oh, I forgot the photo.

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Yep. I'm not sure exactly what I plan to do yet but I think I'm going to have one large tray (or two) below the beam the lathe sits on. Something simple from sheet metal. All the chips that land on the lathe bed or the beam it's mounted to can easily get swept off to the trays below... then I can pull the trays out and dump everything. That would also cover the oil drips from the QCGB... but I may still add something below it just for that so I can keep the oily mess out of the chip tray.

I'm not sure the included chip pan will work, or fit as nicely as something custom but I should give that a try first.
 
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