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  1. From the video, it definitely looks like a...

    From the video, it definitely looks like a centifugal blower of some sort. I am not sure whether forward- or backward-curved blades makes a difference for this.

    It appears that this is...
  2. The motor capacitor will be rated for a higher...

    The motor capacitor will be rated for a higher voltage than the supply voltage. This is normal. 230V motors typically have a 400-450V capacitor.

    Go buy a 25uF, 250V or higher run capacitor. Should...
  3. I think you would rotate the brushes by 90...

    I think you would rotate the brushes by 90 degrees, so that the top two were connected and the bottom two, rather than left & right.
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    If capitalised as MFD, it almost always refers to...

    If capitalised as MFD, it almost always refers to microfarads. I think this may date from periods when all text was capitals and things were not very standard, plus capacitors in the milifarads were...
  5. If you're near to a medium voltage (11kV) line,...

    If you're near to a medium voltage (11kV) line, whatever you want. Typically either single phase 230V to neutral for <=15kVA, or three phase 400V for above that.

    If you're a very long way from a...
  6. I don't think you adequately read the post. Given...

    I don't think you adequately read the post. Given a reversal of the pricing incentives so that daytime power is cheaper, you would expect a substantial reduction in night-time power usage.

    If...
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    WRT starting at 440V, that means connecting the...

    WRT starting at 440V, that means connecting the motor (using contactors) for 440V but supplying it 220V - half voltage. This is similar to star/delta starting but at 50% not 58%.
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    Yeah, I was considering that phase shift might be...

    Yeah, I was considering that phase shift might be an issue. Experimentation might be needed. Ideal would probably be a really fat variac and wind it up, but that's probably cost-impractical unless...
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    Hmm. What about just doing an extreme form of...

    Hmm. What about just doing an extreme form of reduced-voltage starting? Slap enough resistance/autotransformer in line that starting current is manageable, then short them out once up to speed....
  10. Better to lose an extra percent or three shipping...

    Better to lose an extra percent or three shipping it long distance, than shut down renewable plants in areas of excess power and fire up gas a few hundred km away.
  11. The context seemed to be when there is a...

    The context seemed to be when there is a significant build-out of solar and wind, which don't work well at night (wind less so). So pumped storage would be expected to refill during the dip in the...
  12. I think we may be off topic.

    I think we may be off topic.
  13. Hydro and pumped hydro will make a damn good...

    Hydro and pumped hydro will make a damn good start, along with existing nukes. Add some demand management/price incentives and I expect you're most of the way there.

    Power is currently mostly...
  14. The reason the government is involved is that the...

    The reason the government is involved is that the market doesn't account for the external costs very well. It's the 'dumping pollutants in a river' problem but on a large scale. Privatise the...
  15. Minor point: in places with common three phase...

    Minor point: in places with common three phase power, like here in NZ, they don't use three separate transformers - you end up with a single three-phase transformer in a single tank. This provides...
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    Paragraphs and sentences go a long way to making...

    Paragraphs and sentences go a long way to making people willing to help.
  17. 3-phase power is readily available here in NZ but...

    3-phase power is readily available here in NZ but it's certainly not free. Even in a new build situation, you're going to pay a connection fee to the lines company that's about $500 more, plus you...
  18. Three phase doesn't significantly increase...

    Three phase doesn't significantly increase efficiency - higher voltage does that. It does make the utility happy because of balanced power, but that only matters for large users.

    All three phase...
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    Probably 12-24V AC/DC. Do they have a rated...

    Probably 12-24V AC/DC. Do they have a rated current/voltage?

    You'd be looking for a small socketed DIN-rail mount relay.
  20. Need a bigger cap bank too, though.

    Need a bigger cap bank too, though.
  21. Last photo appears to have been taken with a...

    Last photo appears to have been taken with a potato. Confirm you have three phases plus earth from the drive output to the motor? Do you get equal resistances between phases?
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    They're the same way, just drawn differently. ...

    They're the same way, just drawn differently.

    You can also get a submersible float switch like this and have a foot or so of cable between where it is secured and the actual switch. When it floats...
  23. Most of that stuff is unnecessary, and is the...

    Most of that stuff is unnecessary, and is the manufacturer covering their ass. It's likely that if you read the full manual, most of them have exceptions stating when they are not required.

    The...
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    Usually you'd use a beam sensor, but the problem...

    Usually you'd use a beam sensor, but the problem is making sure it's blocked when you put something on the conveyor. You may need multiple or a curtain-style sensor. Easier to pick up off the bin...
  25. Motors up to 4kW are typically 230/400. Motors...

    Motors up to 4kW are typically 230/400. Motors 5.5kW are typically 400/690. Using a 400/690 motor allows it to be started star/delta on 400V.
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