# Soild state phase converter has anybody used one on a Bridgeport



## bobdog (Oct 27, 2017)

Looking at a  soild state phase converter for powering my 2J head bridgeport with 1 1/2 horsepower 3 phase motor. Has anybody used one . They sell them at H&W Bridgeport rebuilding company . They are all soild state and are only $ 80.00.   They said it works for single phase to 3 phase.  Any opinions ?   Or anybody who have used one.  Was going VFD but have a vari speed head dont need anything but 1 phase to 3 phase... Thanks


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## catsparadise (Oct 27, 2017)

Haven't used one on a mill but I have one converting single phase 240V to 3 phase 240V (UK, not USA) which powers a 3 phase 3hp motor on my Harrison M300 lathe. Works a treat. Any switching needs to be rearranged though - generally the solid state converters don't like switches between the load and the converter. Input single phase goes straight into the converter & use the low voltage control signals to turn the motor on/off or reverse.

Rob


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## Wreck™Wreck (Oct 27, 2017)

Are they drives that output 3 phase AC from single Phase AC input like a VFD but without all of the bells and whistles?


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## JimDawson (Oct 27, 2017)

The price seems reasonable.  If you can live without the variable speed of a VFD, then sounds like a good plan.   Having said that, even though I had a veri-drive on my mill, I still found the variable speed function of the VFD useful.  It was easier to turn a knob than to crank a handle.


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## Eddyde (Oct 27, 2017)

The "solid state" (Phase-a-Matic) style converters work but they derate the horsepower of the motor by a third, so if you have a 1 ½ hp motor it will only produce 1 hp. A VFD will give you full power and speed control for only a few dollars more.


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## CluelessNewB (Oct 27, 2017)

It's still just a static converter but has solid state relays rather than mechanical relays.  Yes you would still only get 2/3 of the power.


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## Ulma Doctor (Oct 27, 2017)

as a suggestion,
if you are going to use this type of phase converter you may want to install a momentary switch on the generated leg.
otherwise the converters potential relay will be called to work every time the voltage dips. this will shorten the life of the converter.


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## jmarkwolf (Nov 2, 2017)

I've got a TECO VFD on my Bridgeport Series 1 J-head.

Works famously.

You can't use the big motor reversing drum switch with a VFD however. Wire up the control panel as recommended for reversing, variable speed, emergency stop, etc.


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## projectnut (Nov 2, 2017)

I have 3 machines in the shop running off static phase converters.  A 1 1/2 hp Bridgeport mill (J2J variable speed head), a 2hp Sheldon Lathe, and a 1 hp Racine power hacksaw.  The Bridgeport has  a 20 year old 1 - 3 hp HD Phase A Matic.  The other machines have American Rotary Phase Converter brand 1/2 - 3 hp solid state converters.  All the machines are worked hard and none suffers from lack of power.

As mentioned when using a static converter the horsepower is roughly 2/3 the rated motor hp.  The 3rd phase is only generated on startup, so essentially the motor runs on single phase once it's started.

I would suggest going with the American Rotary 1/2 - 3 hp model.  They sell for $65.00 with free shipping from the companys eBay store. 

https://www.ebay.com/itm/Digital-Sm...692360?hash=item5679811dc8:g:CAwAAOSwVm5Y~oYa

 If you use a phase converter the original machine controls can be used.  If you go to a VFD the original controls may need to be disconnected.  Alll motor functions (forward, Reverse, and speed changes) need to be done through the VFD


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## Bob Korves (Nov 3, 2017)

projectnut said:


> If you use a phase converter the original machine controls can be used. If you go to a VFD the original controls may need to be disconnected. Alll motor functions (forward, Reverse, and speed changes) need to be done through the VFD


It is quite possible to rewire and use the existing drum switch to control the VFD spindle on/off function.  It will be major overkill for the tiny current being controlled, but it is already installed on the machine and can be put back to work after the VFD installation.


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## BGHansen (Nov 3, 2017)

I have a static phase converter on my 2 HP Bridgeport.  As mentioned above, only get 2/3 of the rated power, so I'm running at 1 1/3 HP instead of 2 HP.  However, Series 1's with a step belt drive are 1 HP, so I figure the 1 1/3 is fine. 

Bruce


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## projectnut (Nov 3, 2017)

In my case both the mill and the lathe have built in speed change controls that would no longer be functional.  The lathe, a Sheldon MW-56-P uses a 120 volt gear motor control spindle speeds by opening and closing sheaves on a Worthington AllSpeed drive.   There are no change gears except for threading.  The mill also changes speeds by using a manual crank handle to open and close a sheave.  In both cases the motors run at a constant speed while the sheaves control the spindle speeds.

Here's a link to a similar lathe on eBay:
https://www.ebay.com/itm/Sheldon-EM...307688?hash=item51f694f328:g:zg4AAOSwXYtYxuAt

Note the control panel and tachometer on the headstock.  The buttons on the top row of the  panel are, Reverse, Forward, and Stop.  On the bottom row is a power on light, Slow (spindle speed), and Fast (spindle speed).  This panel would have no functionality if a VFD is used.  To further complicate things you would have to figure out how to rewire the gear motor or control the spindle speed by changing motor speed.

I chose the simpler route of installing a static phase converter.


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## derf (Nov 3, 2017)

I have a manual Bridgeport 1-1/2 hp with a static converter that was installed 20 yrs ago. It worked well for about 2 yrs, then it started blowing fuses for some reason. I took the converter back to the vendor and had it checked, but it checked out fine. So I went with the next bigger unit and haven't had any problems since. Yes, it puts out less power. If I were to do it today, I would go with the vfd. Last year I installed a vfd on my 2hp Bridgeport CNC mill, and eliminated the vari-drive using a solid pulley set up for a poly vee belt. It has more power to the spindle than it did originally.


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## benmychree (Nov 3, 2017)

I bought a static phase converter and wired it to a 5HP 3 phase motor, added some oil filled capacitors between the manufactured leg and one of the single phase legs and ended up with a cheap rotary converter that runs all the machines in my shop.


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