Small or home made sawmills

Jan,
Guy in New Zealand (YouTube= CNC Machining is Fun) uses a light bulb in series for a soft start. Of course his is 240VAC single phase to a circular saw, to avoid tripping his off-grid inverter. May be able to make something like it with a light bulb on each phase, with a 3-circuit push button (Industrial surplus or you might as well get a factory made soft-start), normally closed, to “short out” bypass the lamps for full speed operation. Could be a bit “Rube Goldberg”. I don’t think fuses are all that cheap anymore… I would try to avoid that inrush current when starting the motor. Once started, it won’t use much more current than the old motor until you really start pushing the saw harder in use.
Or I could be full of Shine-ola… :cowboy_hat_face: :grin:

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Thanks Mike. I bought one like this, just trying to figure out how to wire it up.

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For my old tig-welder (industrial surplus) single phase 63a (actually between two phases 400v)
I use a heating element from a boiler (elpatron) 9kW in series when starting, just first 10 seconds, then bypass it (short it out) this single phase transformer has a enormous surge current when starting, fuses pop’s like popcorn.
And yeah, i know, you should not run a welder that needs 63a on your home 3×16a, but as long i don’t crank it up too much it works :smiley:
My axle chunker i direct-start 7,5kW 3 phase 400v, works 8 out of 10 times, if wife doesn’t run anything else in the house :smiley:

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Jan,
Hope it comes with a diagram! I would think, based on what it is, would just have “Line” inputs Phase 1,2,3, and “Load” outputs, letting the switch do the work in between.

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Hi Jan, no trouble wiring these, you need more wires between y/d start and motor, 6+ 1ground, you have to remove the bridging plates in the motors connection box.

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Hmm, easy?

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Ouch! That is a terrible wiring schematic, it also covers other products and uses.
Anyway: schematic marked -12- is the one you should use, those bridges drawn, are they in place in the contactor? Short wires, jumpers, or small metal u-shaped connectors?
In that case it’s pretty much forward, L1, L2, and L3 are phases input. The rest i have to “decipher” some.

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And here is a fast-drawn blurry sketch of how most European 3phase motors look in junction box.


Top pic is with jumpers/bridges removed, how it should look like when you attach a y/d start.
Bottom pic is how it probably look right now, connected for d or delta (triangle) 400volt direct start.
(Those round spots with a line should represent the pole connector screws.)

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Jan, as Goran said, adheres to the scheme -12- …

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Goran, I apologize for interfering, you draw better than me, without a doubt :grin:

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Thanks boys.
Will try to see if I understand this, without the engine starting to smoke.

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Jan, VERY important warning, stick to the markings and schematics and connect the wires that way. Nevertheless, it is good to test the direction of rotation by switching the switch to a star and then connecting the cable to the mains, do the same for switching to a triangle, if the direction of rotation is the same in both positions, you have connected correctly. The diagram I drew is NOT good, here is the picture, Goran is much better than me.
t_20160812_140330

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No Tone, i don’t think anyone draws better, i think we both made it understandable, and you found the picture i searched for, the one to find under the lid on junction box :smiley: :+1:

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Ha! Good it is 3-phase households Europeans talking to 3-phase household Europeans.
Only Industrial Electricians here North America must learn and use 3-phase.
For us common folk it is split-phase AC power:

Wikipedia because it allows good translation into German, Swedish, Italian, French, Spanish and even Slovenian, Ukrainian, Russian and Finnish. And is simple plaintext terminology.
End of article read the blue link to “shared neutrals” and see that Al F. was correct. And could get a prize for his simple direct answer.
Read the beginning of the 3-phase article for some more of the WHY’s? split-(single)phase gets used instead of 3-phase:

S.U.

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That was a good idea, I’ve been thinking about how to test the rotation in y and d. :+1:

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Oak 2 X 20s with one live edge . Just about all me and the mill could handle :face_with_raised_eyebrow:


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They are heavy things, what do you need them for?

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How long has that log been down? I know my 420 cc preditor couldn’t cut those but I have never cut freshly felled wood.

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Good morning Jan

They belong to a customer that builds houses . In the last few months I have sawed several thousand feet for him . About two thousand $

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Hello Mr. Tom .

Not sure how long it has been down . It is a customer log that he hauled in . It still has the bark on it and I would guess it has been down six months to a year .

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