Need info on VFD

Canus

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My 10 hp RPC just crapped out so am considering a VFD to replace it. I was using the RPC to power my 16" South Bend and my J head Bridgeport mill (never at the same time). The lathe has a 3 hp motor and the mill has a 1-1/2 hp motor. Am considering a 3 hp VFD to be used with both machines. Don't plan on using the VFD to regulate speed just to provide 3 phase power. Can the VFD be wired so that it will work with either machine or would I need a separate VFD for each machine? Also would prefer American made VFD so would appreciate recommendations.
 
Good luck finding an American built VFD, but there are a number that are built offshore for American manufactures, to American specs and are supported by them. My favorite are the GS2 and GS3 units from Automation Direct. https://www.automationdirect.com/adc/Shopping/Catalog/Drives

While it would be possible to wire a single VFD to run either motor, that would certainly not be my first choice, especially given the difference in HP. I would recommend a properly sized one for each machine. Once you have the variable speed available you will wonder how you got along without it, even with a variable speed head on the mill if equipped.
 
Why did your existing rpc "crap out"- could it not be fixed cheaper than buying new stuff?
Just sayin'
mark
 
I have a G2 and both my machines are tied into it. Works just fine. I put a safety interlock (two 3 pole contactors) and a selector switch only allowing one to run at a time. You could do it with plugs fairly easy as well. I’m not familiar with any US made frequency drives I suppose Allen Bradley maybe but I’d assume all the components are from China or Japan.
 
As long as it is not one of the VFD's that needs to know all about the motor it drives, I do not see an issue. I have swapped VFD's from one motor to another, without any reprogramming. Right know, I temporarily borrowed one from a drill press, to use on my new to me Sothbend 16".

Its probably just paranoid, and a waste of money, but I have all my VFD's rated for twice the motors rating (3HP VFD, powering a 1.5HP motor). For the little difference in price, I am thinking it will help if the VFD is not working near its capacity.
 
I agree with Jim in this case for several reasons, but with one caveat. Using the same VFD for both machines using the same parameters is not a good choice. What can be done is some VFDs allow you to setup two separate parameter files, one for each motor, you can switch the motor parameter files based on a programmed input. You cannot use the machine motor switch/contactors to control the VFD output, you need to program the VFD low voltage inputs for the VFD run commands. Since the run commands and mode of operation would be different between the lathe and the mill, it can get messy quickly. At the end of the day if this is a long term replacement you would be better off using a dedicated VFD for each machine. Something like the 2 Hp Teco L510 ($175) on the mill, or better yet a GS3, WJ200 or other mid priced VFD would be better suited for the lathe. The Teco L510 cannot accommodate an external braking resistor which is a requirement on a lathe in particular of that size.

If you are looking for a drop in fixed 60 Hz single phase to 3 phase system, there is the Phase Perfect converters, but they are very expensive, so more practical for powering multiple machine or CNC machines.

I am not sure if any VFDs are American made, and most of the components will be offshore, although you can go with a US brand like ABB which have a good reputation. I mostly install/work with the Hitachi WJ200 and the Yaskawa V1000 series. Both are widely used, along with the Automation Direct (GS3), and probably have better support for these brands from others in this forum. Automation Direct is a great US company and very good technical support. At the end of the day, if you want just a plug and play solution and do not need the VFD features, it is probably both more practical and cost effective to get/build a 5 or 7.5 Hp replacement RPC.
 
For markba633csi I took the pony motor to the repair shop today to have it tested. If it needs to be rewound it would cost >$400. Won't be putting that amount of money in it as I can find a used one for well less than that. Still haven't decided if I will stay with a RPC or will go with a VFD (or 2). The RPC has worked well for me for the last several years and I can easily switch from lathe to mill with no problem. Will have to make a decision in the next few days.

A special thanks to all who have provided input to my question, you guys are great.
 
I’m not familiar with any US made frequency drives I suppose Allen Bradley maybe but I’d assume all the components are from China or Japan.

AB PowerFlex drives are designed in the US and built both here and overseas depending on which model you are looking at. They are killer drives, but can be on the more expensive side
 
Got a call from the motor shop informing me that there is no problem with the pony motor of my RPC. Guess the problem lies elsewhere. Will hook everything back up tomorrow and thoroughly check all other components and wiring. Wish me luck. Again thanks for all the informed information.
 
Rather than using a pony motor, I just used a static phase converter to start my 5HP 3 phase motor and added oil filled capacitors to balance the phases; makes a pretty cheap RPC ---
 
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