VFD for Bridgeport Mill

The electrical noise they refer to is noise over the power wire from the drive back upstream to the panel then to all the panel circuits and the power company transformer. Then off to the neighbors and ultimately the dam or steam plant or where ever you power comes from. It can not be totally stopped but it can be controlled by using inline filters in the power wiring both into and out of the drive. The shielded control wiring is to protect the drive from outside sources. Like a ghost starting your mill up. Not to protect outside sources from your drive.

The two pole contactor the previous poster refers to should be installed as the first item power enters coming into the control cabinet. Two pole for single phase, three pole for three phase.

My 2hp Bridgeport is connected exactly as you wish to do I believe. VFD is used for generation of a three phase supply of power, acceleration and deceleration of the drive motor. Forward and reverse direction control. All speed control is via the Reeves Drive on the mill its self. I have a digital tach but have never installed it as I trust what Bridgeport wrote on the dial to indicate speed. I don't find exact speed control to be that beneficial or important. Whether the spindle is going 950 or 1050 when you want 1000 is no big deal. As long as it is close to 1000.

As for voltage, read your supply value. Enter that value when programming the drive. Same for amperage, cycles, service factor and other values. Just enter what is on the motor nameplate. No secrets there.

The pedestal of my mill has a door opening into the pedestal column. I fabed a backplate and mounted the drive and terminal strip in there then fabed up a pushbutton box to mount my pushbuttons in and mounted it on an articulating arm under the DRO. You have a good idea and I would not change a thing on mine.

If you drag a neutral wire in with the power wiring you can grab one leg of the power and use it to power your table drive, DRO, coolant pump, etc. Guessing you will use a 240v, 20a branch circuit to feed the mill. Be sure and tap this power ahead of the drive after the power relay. I don't use this relay option, nothing wrong with the idea I guess I don't figure my VFD failing very often.

Good drive can be found for not a lot of money so you do not have to live with a rice burner. And Hitachi is one of the best, but then it is Japanese.
 
Man you guys are a wealth of experience. Thanks.

I'm traveling for work and can't play in the shop until Saturday, but my GS2-22P0 from Automation Direct has already arrived, sitting at home waiting to be installed. I really don't anticipate any issues in hooking it up, but it's good to see how others have done so. It's a 1 phase input model with a POT and defaults that match my application well.

As to the shielding and up-streaming, I'm not 100% convinced. A long time ago I installed a car stereo system without good shielding. The low wattage output audio run from the factory radio head to the trunk mounted amplifiers, was unfortunately routed alongside the power supply cable for the high draw amp. Induction interference resulted in the initial installation turning the new sound system into an audible tachometer! At lower radio volumes, it was almost unbearable. Once I re-ran the high amperage power cables a different route than the thin low amp audio cables, the problem went away.

One problem I may have Saturday afternoon, is that the motor data plate is inline with the manually tensioned collet draw bar. Over the years, sloppy wrench working, undoubtedly at the hands of elf like, chain smoking machine operators, has dinged up the data plate so badly that it's almost illegible. The H.P. stamp was the worst. I was not entirely sure what HP the motor was until I did some research on the machine and found the original factory motor choices were limited to two, 1.5 and 2. Only that way was I able to eliminate a few of my guesses. I'm 95% sure the Amp column is stamped 5.2.

While demoing the machine, the previous owner (short chain smoker) was unaware of the bare wires in the power feed cord that he draped across the mill table. They shorted out of course and smoke emanated from the X axis power feed, which he insisted on continuing to prove that it worked. It may be shot now and was discounted from the price. Assuming it's toast, what's the best way to handle that? Ebay discount axis feeds for a similar replacement? or look at stepper motors and consider marching towards a CNC retro fit with the ability to yield to program control?

Is there a discussion area more suited for older conversions to CNC?
 
Mine's now working. Thanks mostly to Mr. Kelly's video! Here's my video that may fill in some gaps. Warning I like to ramble once I figure something out.

[video=youtube;FsN4w6l23xc]http://www.youtube.com/watch?v=FsN4w6l23xc[/video]
 
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Glad to hear you got it up and running. I'm sure you'll have no trouble getting the controls set up.
-kelly
 
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