Roatary Phase converter ??

[ultrarunner]

Maybe I just got lucky powering my 1 hp tape mill with a 1 hp slave motor?

Really have not had a single issue and it has been decades... don't even need a rope to start the 1 hp slave... I can twist the shaft with my fingers and it starts just fine if I am quick.

 

[Big Barn]

Maybe I just got lucky powering my 1 hp tape mill with a 1 hp slave motor? Really have not had a single issue and it has been decades... don't even need a rope to start the 1 hp slave... I can twist the shaft with my fingers and it starts just fine if I am quick.

I had to google 'tape mill'. Very interesting and too cool!!

Terry

 

[ultrarunner]

It's an old Bridgeport tape mill with Slo-Syn controls... point to point with a third function rotary table... nothing like the continuous path machines today... NC vs CNC

 

[muddstopper]

Been away for a fw days and lots of good info posted. I have sort of talked myself out of getting the old mill. A mill without tooling is sort of like a car without gas, Looks good sitting there, but it aint going to get far. My experience with machine equipment is that the equipment is cheap, its the tooling that cost you. With all the irons I have in the fire right now, if I bought the mill, it would just sit around until I had a real need for it and then I would spend a bunch just getting it ready to work. I dont think the mill is going anywhere soon as he isnt advertiseing it for sale, so maybe it will still be there when I am ready for it. I'll probably go visit the owner this wkend and check it out a little better, see if he'll let me make a few chips or something. He's got the original manual for the machine, I might just spend some time reading thru it.

As for the converter, I think I am going to go ahead and try and build one. I wont be under any pressure to get it built and I can just keep a eye open for the right parts. I'll probably go ahead and pick up the 25hp 3phase motor I was offered, even tho it is way bigger than anything I might possibly need. I can mess with it and as long as I can fiddle around without spending any money, I should be able to learn a little about how to build a rotary converter and either sell or trade it for what ever size i do end up needing.

 

[Shield Arc]

I assembled a phase converter about 30-years ago. I ran a 1-ton chain hoist, and a 18-inch chop saw I built. Mine has such a high pitch scream, it will drive you crazy in no time at all. :confused2:

 

[woodlandfarms]

Silly question... in the end not that important but I assume that to run a motor phase converter the motor will draw electricity as well as the device that needs the 3 phase. What I am getting at is that to provide 3 phase in a non native environment your electric bill is going to go up. Not that this really matters, I doubt many of us use these machines on full day in day out basis but intrigued.

 

[Big Barn]

Silly question... in the end not that important but I assume that to run a motor phase converter the motor will draw electricity as well as the device that needs the 3 phase. What I am getting at is that to provide 3 phase in a non native environment your electric bill is going to go up. Not that this really matters, I doubt many of us use these machines on full day in day out basis but intrigued.

Interesting story. Please do not question me on the technical aspects of it as I am totally ignorant but...

Years ago an elderly retired machinist/inventor/genius friend had a converter in his basement workshop to run his 3 phase welder. He said when welding the meter would actually run backwards. His comment at the time was the more he welded the more money he saved.

Sadly he passed away many years ago. I wish I had the time back then to pay more attention. Terry

 

[newbury]

<snip>
As for the converter, I think I am going to go ahead and try and build one. I wont be under any pressure to get it built and I can just keep a eye open for the right parts. I'll probably go ahead and pick up the 25hp 3phase motor I was offered, even tho it is way bigger than anything I might possibly need. I can mess with it and as long as I can fiddle around without spending any money, I should be able to learn a little about how to build a rotary converter and either sell or trade it for what ever size i do end up needing.

Be careful going too big.
HP requires amps. Check to make sure that whatever you are going to hook it up to will have the amps. No sense buying 25 HP at $15/HP if the max you can use is 10 HP.

Plus they are HEAVY. 25hp may be about 350 lbs. My 10 HP is about 150 lbs I think.

 

[CNC Dan]

Silly question... in the end not that important but I assume that to run a motor phase converter the motor will draw electricity as well as the device that needs the 3 phase. What I am getting at is that to provide 3 phase in a non native environment your electric bill is going to go up. Not that this really matters, I doubt many of us use these machines on full day in day out basis but intrigued.

The converter motor is not loaded, so it won't use much power.

But it may need large wireing, to handle the large currents it may need. The current will be out of phase with the Voltage, so Power draw will be low, but the current may be high.

 

[newbury]

The converter motor is not loaded, so it won't use much power.

But it may need large wireing, to handle the large currents it may need. The current will be out of phase with the Voltage, so Power draw will be low, but the current may be high.

What I was trying to explain was that getting a 25hp converter would probably enable him to power 18 hp of equipment, which when operating will take a lot of amps. If he tries to run 18 hp of loaded equipment off a 40 amp breaker I think it would be a no go.