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Running a 3ph on 1ph Power- Which method?

Many switches have been installed between a vfd and a motor.
An example would be a bank of vfd's in a motor control room where the motors are installed elsewhere, like a cooling tower fan motor on a roof at a factory. A disconnect would be installed near the motor in this case and that is a switch.
Or a conveyor system run by multiple motors controlled by vfd's, here again maybe a few safety's and a disconnect are installed downstream of a vfd.
A reversing drum switch can be installed on a lathe between the vfd and the motor. You probably don't want to be reaching out to the vfd for your main control of the machine anyway.
 
You might be careful using acceleration, or breaking with your lathe. 1. Threaded Chuck's can fly off. Gears can shear, and gear shafts shatter. Electric motors have extreme torque.
 
Many switches have been installed between a vfd and a motor.
An example would be a bank of vfd's in a motor control room where the motors are installed elsewhere, like a cooling tower fan motor on a roof at a factory. A disconnect would be installed near the motor in this case and that is a switch.
Or a conveyor system run by multiple motors controlled by vfd's, here again maybe a few safety's and a disconnect are installed downstream of a vfd.
A reversing drum switch can be installed on a lathe between the vfd and the motor. You probably don't want to be reaching out to the vfd for your main control of the machine anyway.
What is your qualification in this area? So what if a disconnect switch is installed between a vfd and a motor in a remote location. It isnt generally turned off when the motor is running except in an emergency is it? Most people run their vfd controls right to where the other machine controls are. You can hook up a reversing switch to the vfd. That is the proper way to do it. Im not gonna waste anymore time with you but dont spew your incorrect info to the OP. In case youre wondering I hold a Master Electrician License in Michigan with 30 years experience
 
I started doing electrical work two and a half weeks ago.
I don't think I am spewing just talking from experience, another example from the job im currently running: the control cabinet for the elevator houses a vfd with only 2 motor contactors downstream of the drive. The booster pump also has a pressure switch downstream of the vfd also.
Back to the op there is nothing wrong with installing a drum switch downstream of a vfd to a motor on a lathe. But hey this is America do it however you want!!!
 
I started doing electrical work two and a half weeks ago.
I don't think I am spewing just talking from experience, another example from the job im currently running: the control cabinet for the elevator houses a vfd with only 2 motor contactors downstream of the drive. The booster pump also has a pressure switch downstream of the vfd also.
Back to the op there is nothing wrong with installing a drum switch downstream of a vfd to a motor on a lathe. But hey this is America do it however you want!!!
There is plenty wrong with installing a drum switch downstream of a vfd. So youre talking from 2-1/2 weeks experience and you think you know everything and you can give a guy advice about his electrical installation and tell guys with 20 years of experience they dont know what theyre talking about? You are not to bright. You do your electrical work without knowing what youre doing and sooner or later youre going to have big problems. You think they would have 5 year apprenticeships if you could learn it all in 2 weeks. Those rats you work for must have really brain washed you. Someday youll find out what i say is true if you live that long.
 
VFD is on the way.

I went with a TECO FM series. Trying to keep it all as simple as possible. I will have it hooked up so that I can use all the controls on the lathe. Although using the speed control and setting up proximity sensors is neat it's beyond what I want at this time.

Thanks for all the help. I'll update when it all gets installed, hopefully by the middle of July.
 
VFD is on the way.

I went with a TECO FM series. Trying to keep it all as simple as possible. I will have it hooked up so that I can use all the controls on the lathe. Although using the speed control and setting up proximity sensors is neat it's beyond what I want at this time.

Thanks for all the help. I'll update when it all gets installed, hopefully by the middle of July.
Don't forget , your wife will read this $$$$$ !
If she is like mine , let her buy some shoes , everybody wins .
 
It seems you know enough about it to know its generally a no no to switch power wiring between vfd and motor it controls. That can result in smoking your vfd.


My certified electrician wired my VFD wrong and smoked the motor. Voltage needs to go from the VFD to the motor and your switch to the proper place on the VFD. My drum switches on both of my Bridgeports are connected to the proper place on the VFD with door bell wire. I did add cheap braking resistors to them so that I could have instant braking when needed. You can run several machines with a Rotary, but I think you would need a VFD for each machine.
 
I went and looked at a lathe today. It's a Harrison M300 in real nice shape. Price is right and I think the size would work well for my current and future needs. The motor is 3hp, 3ph.

I currently have 220 1ph in my garage which is where I plan to set this up. Can someone explain the major advantages/disadvantages between:
Static converter
Rotary converter
Variable frequency drive

I'm trying like heck to get all my ducks in a row to start gunsmithing on my own stuff but am not well versed in electricity.

Thank you in advance.
Vfd is the best way to go
 
Contactors do not belong down stream of a vfd for any switching purposes besides emergency disconnects and motor selection with the proper associated interlocks. There is no good reason to have a drum switch between a motor and drive. Half the drives job is to reverse, properly brake the motor to stop, reverse, accelerate. Opening the motor feed of a vfd will result in drive output voltages going through the roof, also results in tons of RF noise during the process.

But what do I know...21 years as an electrician, and working on my PhD in electrical engineering.

Vfd is an extremely effective way to utilize single phase sources for three phase loads.
Rotary phase converters get the job done, they can require some additional attention and someones some trial and error, and tuning.
Phase perfect is a much better path than the rotary especially for multiple varying loads. My shop is single phase, and run a mix between the phase perfect for the larger machines, and single phase sourced VFD's for less than 5hp machines.
 
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I have a 1980 jet 1340, the slowest speed was 90 rpm's. now with the VFD I can go as slow as I need .. I don't go below 30 hertz but I could for short periods20170428_182855 (640x360).jpg
 

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