3 phase to 1 phase questions

Jody Treadway said:
My machining "skills" involve a carbite deburring bit and a grinder.
Plus, Fletcher Machine shop is lliterally next door. :laughing:
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Holdup? You think you'll actually USE the bridgeport? :laughing:

People with such machines don't use them, they just add to their collection of things to have to fix. ;)

Plus there's a shit ton of gears in a good one, and I heard that's kinda your thing.
 
With that said, they also have driveshafts, so maybe you should stay away :flipoff2:
 
Jody Treadway said:
That's cold
I assume they have integral step stools?
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Nah, that's why I'm selling the Bridgeport. Bought a Cincinnati Toolmaster and the table and handles are about 8" lower. ;)
 
I have a used 3phase converter i could probably part with cheap if its still laying around
 
These rotary style phase converters are heavy af and LOUD af. Switched to VFDs while back and now its only as loud as a walmart fan, lol.

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ckruzer said:
These rotary style phase converters are heavy af and LOUD af. Switched to VFDs while back and now its only as loud as a walmart fan, lol.

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I have a few of those Eaton powerflex vfds and they have a super annoying feature where after xxxxhrs they indicate a fault and say to replace the cooling fan. I haven't figured out how to make it go away.... Haven't actually tried changing a fan though 😂
 
Mac5005 said:
I’m just here to sidetrack this thread further.

Suggestions on single ph 208-230 transformers? Need to be able to handle 60a.
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Are you wanting to go from 208v input to 230v output? If so, this is where I would tag @Ron so he could explain why its probably not necessary and is just a misnomer.
 
jeepinmatt said:
Are you wanting to go from 208v input to 230v output? If so, this is where I would tag @Ron so he could explain why its probably not necessary and is just a misnomer.
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Yes and it’s not a misnomer.

Difference in different types of 3ph and how that related to voltage achieved at the plug on single phase.

My plasma and a couple of my welders would run better on 230/240v vs on 208. They work fine, but not as well as they could and I see an increased input current compared to the the tag for 230.

That and some solenoids don’t like opening and closing fast on 208 vs 230, and my solution was to use 120v solenoids instead but it’s kinda rigged.

Iirc it’s bc of our 3ph transformers are Y and not delta, so when pulling two hots for 1ph “240” I only have “208” between those legs but still 120 from any leg to ground/neutral.

I really have 125v on each leg and my “208” comes out about 212ish at the plug.
 
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The electrical gurus in here can correct me if I am wrong @Mac5005 but if you are not changing phase you do not need a transformer. You need a buck converter. Theyre probably the same thing hypertechnically, but that's just how I differentiate in catalog/shopping terms.
 
ckruzer said:
The electrical gurus in here can correct me if I am wrong @Mac5005 but if you are not changing phase you do not need a transformer. You need a buck converter. Theyre probably the same thing hypertechnically, but that's just how I differentiate in catalog/shopping terms.
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The phase converter changes the number of phases (single to 3 phase) , the transformer changes the voltage (230v to 460v). I'm pretty sure a buck converter is basically just a step down transformer, which would do nothing for the phase change, and is the wrong direction on the transformer. Boost transformer/converter would get the voltage right.
 
jeepinmatt said:
The phase converter changes the number of phases (single to 3 phase) , the transformer changes the voltage (230v to 460v). I'm pretty sure a buck converter is basically just a step down transformer, which would do nothing for the phase change, and is the wrong direction on the transformer. Boost transformer/converter would get the voltage right.
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They're buck-boost. They'll do either depending on how the taps are set.
 
Late to the party but rule of thumb for running a 3 phase motor on single phase is use a 3 phase VFD rated for twice the motor HP.

A transformer is AC , can be Step Up/Down or just Isolation
A Converter goes from AC to DC , can be Buck/Boost

A typical VFD uses the incoming AC power to charge a DC Bus on Drive, then uses an inverter to generate 3 phase power for running the motor.
A phase converter works in about the same way
 
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