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Recent content by Eclectic

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    Can I use VFD + Idler Motor = 3ph Bus?

    Yes, at this point, though, I'm just wanting to use the motor windings as a transformer, or with caps as a filter. I don't care about pulling or pushing mechanical power from the thing... If someone could point me to a source of cheap, available 5-10 kva 3 phase transformers, I could care less...
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    Can I use VFD + Idler Motor = 3ph Bus?

    Ok, forget the motor/generator/rotating core/squirrel cage/rotor slip/flywheel thing entirely for a moment. If I was to cut off the conductive shunts on the ends of the rotor, I would for all intents have turned the motor into a transformer, right? There would be a closed flux path through...
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    Can I use VFD + Idler Motor = 3ph Bus?

    Dave, yes, that's more of the kind of answer I was looking for, in fact, the small amount of slip that does exist may actually be blocking the magnetic flux path through the rotor, impeding transformer action. The links I came up with on the google search are actually very educational and...
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    Can I use VFD + Idler Motor = 3ph Bus?

    PeterH: I don't think your posts are a waste either: just the "It can't be done" attitude. You would seem to be saying a rotary phase converter can not possibly work because it is an induction machine. A google search on "induction generator" has been very helpful...
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    Can I use VFD + Idler Motor = 3ph Bus?

    Peterh: You are throwing terms around as if they were pronouncements from GOD. You are not giving any REASON why the arrangement is not working as a transformer with a rotating core element providing some resonant filtering action at the operating frequency. The goal here is to come up with an...
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    Can I use VFD + Idler Motor = 3ph Bus?

    You may rest assured. I would prefer experimental evidence. I haven't heard anything yet that would convince me that an experiment is not worthwhile. (Aren't you glad we don't live in Deadwood?)
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    Can I use VFD + Idler Motor = 3ph Bus?

    Yes. But. I'm not talking about one motor driving another as a generator. I'm talking about a single motor with two sets of windings cowound around the same stator poles. The VFD is driving one set of windings 3 phase, the other set of windings is the output, so as to isolate the VFD from...
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    Can I use VFD + Idler Motor = 3ph Bus?

    Do you have any references? I'd think the rotor would be excited by the driving coils, and at a minimum, there should be a transformer action from two sets of coils cowound into the same stator poles. I'm planning on testing the idea, but wondered who else might have actually tried it and...
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    Can I use VFD + Idler Motor = 3ph Bus?

    A lot of high horsepower 3 phase dual voltage motors have two sets of windings, parallel for 240V, series for 480V. Has anyone tried driving one set of windings with a VFD and powering a 3 phase bus with the other set of windings? Essentially you would be using the motor as a rotary...
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    Reid 2B Surface Grinder

    I recently bought a used WWII era surface grinder off Ebay that has automatic electric feed. The Y crossfeed mechanism is missing, however. It looks like someone started to repair it and gave up. Does anyone have manuals or repair documentation for Reid Grinders? Anyone with a 2B they could take...
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    Reid 2B Surface Grinder

    I recently bought a used WWII era surface grinder off Ebay that has automatic electric feed. The Y crossfeed mechanism is missing, however. It looks like someone started to repair it and gave up. Does anyone have manuals or repair documentation for Reid Grinders? Anyone with a 2B they could...
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    New Question about 1 VFD for the whole shop.

    I'd think a small 1-2HP idler motor with small run caps between each leg to make it look like a purely resistive load at 60 hz would effectively act like an LC filter/snubber. The caps should take out any high frequency voltage spikes that could damage the VFD's outputs
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