• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

phase converters

Share this page

SilentUnicorn

SilentUnicorn

Yoda
Country flag
Offline
I will soon be the proud owner of an ancient bridgport. it will require 220 3 phase power. i have 220 single phase available, i will need to run it to the garage, about 50 feet. i am looking at using a static box https://www.phase-a-matic.com/StaticModels&Prices.htm Is anyone out there using something similar? i understand that a rotary converter may be better, but they are a bit out of my price range. Any reccomendations on what size wire to use for the 50 foot run? i would like to bury it in the ground. i dont plan on running the machine on a production schedule, just pretty much as a "its there if i need it" deal. any thoughts and comments will be appreciated.


mark
 
That's an interesting device... I'm not sure I'd use one... What exactly is an "ancient bridgeport" and how sensitive is it to a reduction in horsepower? What is the horsepower?

Personally, I would look into replacing the 3-phase motor with a 220V single phase motor of the same horsepower.
 
Hi Mark, Another source would be RonkElectric.com. Either way, its pretty inefficient to go this way, if you do, the key is to make sure everything is sized accordingly. Ian may have something there regarding replaaaaacing the motor.
 
Mark,

I just picked up a 3 phase vertical mill and will be building a rotary phase converter. Take a look at https://www.metalwebnews.com/howto/ph-conv/ph-conv.html The plans are really pretty simple; you can usually pick up a scrap 3 phase motor pretty cheap. I was doing to change the motors out to single phase, but it isn't an option since the power head is 2 speed and reversing. When are you doing this? I should have mine built in a few weeks so I’ll have some first hand info then.

Chris
 
I'll second Chris' message, made a rotary convertor, in the mid 90's cause the static one blew, got a 3hp 3phase motor, some old run capacitors from old air conditioning units
worked for years then got a 5hp added more run caps, now powers a 3.5hp P7 Pullmax,old 2hp lathe, and my old BP. i run the unbalanced self-starting. Good luck tt
 
You don't, really, need a big wire to run your 3HP, 3 phase machine. My best guess without seeing the converter specs is that you could get'er done with 14 ga copper on a 20 amp branch. Let's put a little extra capability out there, incase you want to operate a welder or ???

You'll need "UF" cable for butial (Yes, HD and Lowers carry it) If you want a 25 amp service, use 12 ga copper, if you want 30 A service use 10 ga copper. Be sure to pick up a breaker for this branch, they're a little pricy, but worth the safety factor provided. You'll need to know the make and model number of your breaker box for this exercise.

Good luck
 
Thanx all for the thoughts. It is a 1957, Westbury 1.5 horse mill. tag says it was built in Italy. I built a frame for it to roll around on this week and i hope to get it moved here this weekend, certianly by next weekend. Been retrofitting a space for it in my rather small garage.

that dc motor conversion looks pretty neat. and perhaps i will give that rotory converter a shot.

Mark
 
Another option that I forgot about is to use a variable frequency drive as a phase converter. There are inexpensive drives out there from Hitachi and Leeson (and others) that take 230 single phase and will output 230 three phase. A 1 HP drive is around $250 and a 3 hp is around $400; more than a static phase converter but less than a rotary. I have an applications engineer from a drive company coming into work this week to look at an application so I’ll pick his brain and report back.
Chris
 
Upon mentioning that I needed a phase converter to support my LBC habit, the English sales manager told me to keep my eyes open for a GT6 and that he would send me a used one they had in the shop. So I'll report back with how it works out when I get it.
Chris
 
Heres a pic of my mill. i went with the statc converter, on the advice of my motor man. let ya know how it works.

182610-mill3.jpg




mark
 
VEERY noice, Mark. I'm in envy.

And I see a "Refreshing Adult Beverage" in evidence as well.
 
ya not to bad for 5 bills. need a good cleaning, and i need to finish blocking it up, Picked up the converter today, and hopefully i may get some wire run this weekend. I have to do an exhaust on the DD first tho..


mark
 
Looks good Mark; nice find. I wired up mine today with the VFD and it works fine. It isn't a Bridgeport so it doesn’t have the nice variable speed turret head, but a 12 speed belt setup instead. A side benefit of the VFD is that it now has 12 variable speeds that overlap. I did have to rewire the coils for the starters to the single phase side because the drive would bog down with the inrush current of the motor at high speed and the starter would chatter. Not the most elegant solution, but not bad for free.
 
My son is a mechanical design engineer with a new compnay. He has mentioned that there should be more machines comming on the used market. He company is all digital and computer controlled and won't use the "old" technology. So look around and you may be able to pickup a great deal again.
/ubbthreads/images/graemlins/yesnod.gif
 
Back
Top