PM-1660TL

I installed a VFD on my 1440TL without near the level of understanding you have of your wiring. I am sure you will end up with a great install when you are complete. As I skimmed though your notes above I am not sure I follow why your jog should be disconnected? The not on the faceplate saying jog should not be used for gear changes is accurate, when changing gears you want to move the Chuck by hand to allow for smooth gear alignment. The jog function is great when you are fully engaged in a gear and need to turn your part for alignment or measurement. When your lathe is in a very low gear you often can’t turn the Chuck by hand and will need the jog. With my VFD install I actually added reverse jog to the standard forward jog. Can be very handy when you need to move a part.
 
BladesIIB said:
I installed a VFD on my 1440TL without near the level of understanding you have of your wiring. I am sure you will end up with a great install when you are complete. As I skimmed though your notes above I am not sure I follow why your jog should be disconnected? The not on the faceplate saying jog should not be used for gear changes is accurate, when changing gears you want to move the Chuck by hand to allow for smooth gear alignment. The jog function is great when you are fully engaged in a gear and need to turn your part for alignment or measurement. When your lathe is in a very low gear you often can’t turn the Chuck by hand and will need the jog. With my VFD install I actually added reverse jog to the standard forward jog. Can be very handy when you need to move a part.
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Thanks for that input.

I needed to understand the safety circuit thoroughly so as to keep ALL the functions provided by the factory circuit.

I think there is a jog capability from the VFD: power at alternate very low frequency for a short time. I am at the point where I have modified the circuit drawing to remove certain wires and inject the VFD power, and to be able to extract the required signals to the VFD for forward, reverse, stop. (What the VFD does with the stop signal depends on what physical change was done on the lathe. I'll post my modifications for critical input, if anyone is so inclined.

As I review exactly what control signals are required for the VFD, (I am pretty familiar with the Hitachi manuals now, having studied it several times), I'll keep in mind how to provide the jog functionality, but only when the gears are fully meshed. I have been thinking about how to tell when the gears are in complete mesh for quite a while and have some thoughts on how to accomplish that.

Really, in a perfect world, the VFD ought to know that before it applies power to the motor.

Your input is appreciated.
 
It is one thing to understand how it is wired and how it works, but I guess it all depends on the purpose of the exercise. If you do the basic VFD install, you pretty much leave everything intact except for the high voltage wiring to the forward/reverse contactors and eliminate the overload relay. You then use 1 pole of each contactor to operate the respective VFD input for forward/reverse. Jog with the default wiring will just trigger the respective contactor just as it did before. Alternative is to directly wire the jog to a input on the VFD programmed to Jog. The WJ200 also has a different approach to how the jog is implements, the jog input sets the speed and then you need to simultaneously give a for/rev direction input.

The foot brake switch should be replaced with a dual pole, the instructions and programming would be very similar to the 1440GT basic VFD install guidance, with the motor parameters adjusted accordingly. BIIB outlined most of this in his video, just one of the ways to do it. I would also be a bit cautious on the schematic diagrams provided by the manufactures, they sometimes make changes and do not update the schematic, and as you found the symbols can vary quite a bit. There are different designs for complete replacement systems if that is your approach, but it can take quite a bit longer to do and make sure everything is working the way you want it to be. My first VFD control system took 3 months to design and work out the bugs and programming. I would suggest either go for a simple approach or a complete replacement system as opposed to something cobbled together. You might want to start your own build thread for others to follow.
 
xyz said:
As I review exactly what control signals are required for the VFD, (I am pretty familiar with the Hitachi manuals now, having studied it several times), I'll keep in mind how to provide the jog functionality, but only when the gears are fully meshed. I have been thinking about how to tell when the gears are in complete mesh for quite a while and have some thoughts on how to accomplish that.

Really, in a perfect world, the VFD ought to know that before it applies power to the motor.
Click to expand...
Jog really doesn't have anything to do with gear mesh. You can put gearbox in neutral and still activate jog and the motor will run at jog speed but not the spindle. Using VFD and programming and correctly wiring forward/reverse jog same thing occurs and motor will run at 6HZ if that's what you have it programmed to do. Again with lathe stopped, you can change gearbox, you may have to roll the spindle to get gears to engage, same can happen with leadscrew or feed change. Once gearbox is engaged, you can then use jog, either direction. I even use it for tapping.
 
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