Good point but he does not have an inverter. He is running his motor on single phase from the mains. How do you feel about that
Dan
Putting the cart before the horse…..Three Phase power question???????
- Thread starter Runs With Scissors
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Dan
I would not have a good feeling doing that.Good point but he does not have an inverter. He is running his motor on single phase from the mains. How do you feel about that
Dan
It can be done with a capacitor on one of the phases. Or you jump start it by hand in the desired direction. Otherwise I think direction of rotation may be used as a random number generator.
I believe the only thing inside his Phase-A-Matic box is a start cap and potential relay that kicks the motor off. There may be a front panel switch to select direction. After that T3 is dead.I would not have a good feeling doing that.
It can be done with a capacitor on one of the phases. Or you jump start it by hand in the desired direction. Otherwise I think direction of rotation may be used as a random number generator.
A picture of whats under the hood would be revealing.
Dan
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I don't know....
Inverters are cheap those days. The soft start alone is worth the expenditure to me. Plus speed control if you wish. And a decent motor overload protection. And no fuses tripping with excessive inrush current with bigger motors. And so on ...
Inverters are cheap those days. The soft start alone is worth the expenditure to me. Plus speed control if you wish. And a decent motor overload protection. And no fuses tripping with excessive inrush current with bigger motors. And so on ...
Every machine I have starts and reverses using the OEM contactors. This machine is 30+ years okd and was used in a poiduction shop at Corning for the first 20. It still works flawlessly.
Trying to rewire it to use inverters wiuld be an incredibly expensive waste of time.
Dan
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I agree, I would not do that either. But the original post, and also my problem, was to have bought a three phase machine but only having single phase supply available.
Yes, we have gone far afield. As I said in my initial response:
If its a small machine and that is all you will ever need the choice is simple - buy a VFD.
If its a BIG machine and/or down the line you will have a shop full of 3 phase machines a RPC becomes a very attractive and cost effective alternative.
Dan
Yes - any VFD manual I've seen teaches NOT to use any switch between the VFD and motor.
Im gonna invent a VFD that doesnt care what you wire into it. You could stuff a pizza festooned in pineapple and ham in there and it would still work.
I have used every type of phase converter there is over the years. Started with the cheap ones to run on two legs and then the rotary but once I discovered vfd's I didn't look back!
On my mill, this vfd didn't have reverse so I did the no no and ran it through the switch. But I don't do instant reversing when tapping. Just turn it off and when the spindle stops hit reverse. Simple. All the vfd's are custom set to the machine it is operating, such as setting the start up time on the compressor and grinding machines. Basically soft starting them. And speaking of that...
this is a 40hp rated drive that I use to power the 20hp motor on my big lathe. That is a 20" chuck that you are looking at to give you and idea what the scale is. I set up the drive to start this motor up over ten seconds to manage the amperage draw. I set the readout to show amps and it draws 26 amps on start and it idles at 19 amps. No way I could start this lathe without it because the inrush would pop the breaker.
As you can see, they are all different brands but I have had zero issues with any of them. And most of these have hundreds of different parameters you can set to customize it to the machine. Like I said earlier, speed control and reversing are your main concerns on the mill. Good luck!
Now back to the popcorn.
On my mill, this vfd didn't have reverse so I did the no no and ran it through the switch. But I don't do instant reversing when tapping. Just turn it off and when the spindle stops hit reverse. Simple. All the vfd's are custom set to the machine it is operating, such as setting the start up time on the compressor and grinding machines. Basically soft starting them. And speaking of that...
this is a 40hp rated drive that I use to power the 20hp motor on my big lathe. That is a 20" chuck that you are looking at to give you and idea what the scale is. I set up the drive to start this motor up over ten seconds to manage the amperage draw. I set the readout to show amps and it draws 26 amps on start and it idles at 19 amps. No way I could start this lathe without it because the inrush would pop the breaker.
As you can see, they are all different brands but I have had zero issues with any of them. And most of these have hundreds of different parameters you can set to customize it to the machine. Like I said earlier, speed control and reversing are your main concerns on the mill. Good luck!
Now back to the popcorn.
ken erickson
Well-known member
Equipment
B7100 hst, 2650 front mount snowblower, L2501 hst qa loader
Nice shop!
Is your surface grinder a Harig Super 612? Have you used different RPM's when grinding? I have a Super 612 and have run it hundreds of hours (if not 1000's) with a static phase converter. The bulk of what I ground was hardened knife steels, relatively thin, 3/32 typical. I had considered adding a coolant pump but I never hogged with it and liked seeing my progress. Overheating the work piece was never an issue. My motor is rated at 1HP and prob never ground at more than a 1/3 of that capacity. For me the static converter has worked well.
Runs With Scissors
Well-known member
Equipment
L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
Oh no, my brother from another mother......................Pineapple on pizza should be outlawed sir!!!!!
Runs With Scissors
Well-known member
Equipment
L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
I thank everyone for their input.
Unless I find some sort of very compelling reason not to use one, I have decided that the VFD is going to be the best route for my particular situation.
They seem to be very reasonably priced, and I really like the "variable speed" aspect of using one.
I have read that although it will not be "100% variable" it appears that the degree of variability should suite my needs.
Now to come up with a "proper title" for the write up detailing the move down stairs.......
Unless I find some sort of very compelling reason not to use one, I have decided that the VFD is going to be the best route for my particular situation.
They seem to be very reasonably priced, and I really like the "variable speed" aspect of using one.
I have read that although it will not be "100% variable" it appears that the degree of variability should suite my needs.
Now to come up with a "proper title" for the write up detailing the move down stairs.......
Maybe it should start with, building a 2500 pound capacity elevatorI thank everyone for their input.
Unless I find some sort of very compelling reason not to use one, I have decided that the VFD is going to be the best route for my particular situation.
They seem to be very reasonably priced, and I really like the "variable speed" aspect of using one.
I have read that although it will not be "100% variable" it appears that the degree of variability should suite my needs.
Now to come up with a "proper title" for the write up detailing the move down stairs.......
. Or possibly end with a divorce 
.Maybe:Now to come up with a "proper title" for the write up detailing the move down stairs.......
"How to demolish stairs with a Bridgeport milling machine"
or
"Don't try that at home".
or
"Why I need a ladder now to get into my work shop"
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Perhaps “How many pieces can be removed from a Bridgeport mill” or”How many pieces does a Bridgeport mill become when rolled down a staircase?”
Yes, I have the exact same machine. I run it full rpm but I do have it set to ramp up over a couple of seconds. Same with the shut down. I finally bought a balancer to true up the wheels and it made a big difference in grind quality. I have to admit I am anything but an expert on surface grinding.
Mine is in the basement, I skidded it in four large pieces down the steps on 2x4's. I'll find some pics and post them for you.
I'm sure someone will tell me I did it wrong though
Runs With Scissors
Well-known member
Equipment
L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
Yes sir, it appears that I have some reading and experimenting to do while setting my machine up.
It’s all part of “the journey” I suppose.
