Phase liner PSU

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Apr 28, 2023
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115
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South Central VA.
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X usaf electronic tech.
#42
Then use transformer step up 3phase 480 we have one smaller version 5hp 230 allowed use to test up to 10 HP 480v hoist .
Me too

I had to build a idler motor setup to get three phase Lee It uses a 1/2hp single phase motor to spin up a 25hp 240v three phase motor. When it is spinning then apply single phase 240v to two of the three legs. The 25 hp motor generates the third leg and feeds my lathe and mill and any other items I may get. It good to supply at least 18hp of current load.
 

wattsabundant

Chief Journeyman
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Apr 26, 2011
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878
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Central Ohio
#43
Then use transformer step up 3phase 480 we have one smaller version 5hp 230 allowed use to test up to 10 HP 480v hoist .
My brother bought a 3 phase, 208 VAC, 7.5 H.P. dust collector. To power it in his house I bought a variable frequency drive (VFD) intended for single phase 240 VAC in and 3 phase out. I built a box with start/stop push buttons and a pot to control ramp rate. Uses a 8" flexible pipe from the colletor to the Unisaw. Zero dust on the shop.
 
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May 17, 2023
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Finland via the deep south
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Details, details
#46
Hm, residential power with three phase. I don't see an application for it. Is your panel three phase? WYE or DELTA?
the panel has all 3 phases and a common neutral so you get three (3) 240v legs. If you wanted to wire then together delta then you get 400v phase to phase but WYE you get 240v. Like one comment..."less copper"...most of the wiring in the house is 1,5mm2 for a 16A circuit.
 

wattsabundant

Chief Journeyman
Joined
Apr 26, 2011
Messages
878
Location
Central Ohio
#47
the panel has all 3 phases and a common neutral so you get three (3) 240v legs. If you wanted to wire then together delta then you get 400v phase to phase but WYE you get 240v. Like one comment..."less copper"...most of the wiring in the house is 1,5mm2 for a 16A circuit.
To be precise, in a wye connected 3 phase system, if line to neutral is 240, the line to line would be 415 (240 x 1.732). I'm surprised there is 400 plus volts in a residential panel. I admit to having limited exposure outside the U.S. and no foreign residential expereince. The arc flash in a 240 volt panel is deadly enough. 400 volts is not something a typical homeowner has any business dealing with. My guess is with a moniker of "Pulpmillguy" there is an understanding of the dangers of higher voltages.
 
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Finland via the deep south
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Details, details
#48
To be precise, in a wye connected 3 phase system, if line to neutral is 240, the line to line would be 415 (240 x 1.732). I'm surprised there is 400 plus volts in a residential panel. I admit to having limited exposure outside the U.S. and no foreign residential expereince. The arc flash in a 240 volt panel is deadly enough. 400 volts is not something a typical homeowner has any business dealing with. My guess is with a moniker of "Pulpmillguy" there is an understanding of the dangers of higher voltages.
OK, Mr. Smarty Pants :D...it was a nominal 240V and 400V that I was talking about. Just got back from the shop to verify but here is what I currently have:

Phase 1 238,0 v
Phase 2 237,1 v
Phase 3 237,2 v

1-2 411,5 v
2-3 411,6 v
1-3 411,6 v

And yes, "Pulpmillguy" has had his fair share of experience with elevated potentials in his 40 years wandering around mills.
 
Joined
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Finland via the deep south
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Details, details
#52
Three phase motors are more efficient. Considering that a large portion of household loads are motors it makes sense. A simpler less expensive motor as well.
Actually most small motors are single phase and only big loads like the stove top are wired up 3 phase. All big shop tools over 3 kw are 3 phase. The electric heat has a separate 240 control circuit and then a separate 3 phase supply for the heaters...but each heater is only single phase.
 
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