New 1340GT Coming and Need Assistance with VFD

I would keep the light, get a 50-100w 24vdc PWM power supply off ePay to run it. They run off 100-240 vac. The stock transformer would not work with the Vfd source logic which is vdc. Would use a decent quality linear tracking 2-4w pot, either carbon film or wire wound. Also check Mouser Electronics, I can check if I have a spare and send when I get back from traveling.

I basically bought everything listed on your schematic (lighted jog, 4k pot, etc.). Even bought a metal E-stop switch and the graduated plate for the pot. All from AutomationDirect. Got a shipping notice in about 3 hours. Not bad... :)

Also on the buy list is a 14x12x8 enclosure from the same company. Just waiting on payday. I'm going to make a new control plate for the front of the lathe as well as a different oiling plate for the Norton. I'm liking John's idea of mounting the VFD on the side of the stand, but will have to put plugs/connectors on the box for the high voltage and control circuits so I can disconnect and move this thing a little easier.
 
Bill,

I did a recent build with the VFD box on the end of the lathe in an electrical box, either the headstock or tailstock end works well. You can also put in a breaker disconnect or service disconnect, which I believe should be the default for any machine. On my lathe, I use a long power cord 20A 25' with a 20A plug so I can move it or disconnect it completely (generator cord with one end cut off). It is a 4 prong male plug, as I use 120V for the DRO and possible future accessories. All my control circuits are terminated in spade connected to screw terminals at the relay control box. All the wires and connections are numbered, so only would take a few minutes to unscrew everything. This was a recent build for another forum member, might be good for some ideas. http://www.hobby-machinist.com/threads/acer-trump-1236-vfd-conversion.32910/

A lot of different ways to set it up. If you have any questions, let me know or PM me.

Mark
 
Well Darn Mark, if I'd known you could put together a kit for me I'd have had you do that for me as well. :)

One comment on that thread bothers me though, as I have a 8 1/4" Pratt three jaw set-tru. Is this thing going to throw faults because of it's mass?
 
It was an interesting build project and something different. I did not feel comfortable in providing a untested circuit design/build recommendation and not being able to test it, although this went a bit beyond that and took a fair number of hours. Still, if a forum member gets into a bind with a VFD build, I could put something together for the cost of parts and getting it to you. But the stars need to align.

There is a lot of mass in the 8" chucks, about twice the weight of the 6" and greater momentum/weight at the outer diameter. So you may get a fault with a 1 second stop at higher RPMs, but he was using a Huanyang VFD which does not have the same capabilities and tuning parameters as the WJ200. I think with the braking resistor and the WJ200 parameters I outlined you should be good for at least 800 RPM. If you run into problems, options include: go to a 2 second braking, go to 2 stage braking (2 second total), or there are some tuning parameters to increase the over voltage trip point, change the sampling time for monitoring over voltage and change the braking curve . Lets see if it becomes an issue than we can see about possible changes. I have an 8" combination chuck (~56Lb with backing plate) that I need to turn a backing plate for, I will use this to test the braking and update you on any further programming parameters/changes when I get back mid April.
 
Platt Electrical has good prices on Hoffman NEMA 1 electrical cabinets that will work great for this.

https://www.platt.com/platt-electri...s/search.aspx?SectionID=2&vendors=Hoffman_111

Those look like good boxes... here is the one I used:

http://www.amazon.com/gp/product/B005T94MQU/ref=od_aui_detailpages00?ie=UTF8&psc=1

Perhaps a bit large, however it leaves lots of room for fa cooling fan, intake, master power switch, Hitachi VFD, and some terminal blocks.
 
Electrical box needs to be at least 7" deep on the interior dimension, the Amazon one listed is not deep enough.

WJ200 Dim.jpg
 
The box I'm looking at is big enough to put a little 24v dc switcher in there.
 
Electrical box needs to be at least 7" deep on the interior dimension, the Amazon one listed is not deep enough.

View attachment 97911

Yes, if one wants to mount the VFD on the back of the box... I am mounting the box with the long side vertical, and the VFD mounted sideways on one of the long sides. It is not hard to see and work the buttons on the VFD... and IMO once it is set up... I probably will not play with it much.

If I am wrong in this assumption.... would appreciate guidance... :)
 
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