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Type: Posts; User: Jraef

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  1. Replies
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    271

    There is no other fuse on the drive, so as JST...

    There is no other fuse on the drive, so as JST said, it's possibly a bad internal power supply and not repairable.

    But there is a SMALL outside chance that it is actually just a problem with the...
  2. VFDs don't "like" reciprocating compressors much,...

    VFDs don't "like" reciprocating compressors much, you need to over size them because of the "stroke" loading. I recommend that a VFD be over sized by 50% for a recip compressor, I have never had...
  3. If you over size it enough, it should work. The...

    If you over size it enough, it should work. The "enough" part is something that the mfr has to agree to though. Lots of people ASSUME that 50% de-rate is fine, because it IS fine on SOME drives,...
  4. Replies
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    2,109

    The zig-zags in the POWER circuit would have been...

    The zig-zags in the POWER circuit would have been the heater elements (coils). The zig-zags in the CONTROL circuit would be the solenoid coils. That's an old European standard prior to the...
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    Just a note on using high carrier frequencies. It...

    Just a note on using high carrier frequencies. It increases the switching rate of the transistors, which thereby increases the switching LOSSES in the transistors. So responsible VFD mfrs will...
  6. Whether or not a VFD can accept single phase...

    Whether or not a VFD can accept single phase input is really just about how the VFD mfr designed their power supply for the electronics inside. Some mfrs chose to tap off of the DC bus with a DC-DC...
  7. There are devices called "boost converters" that...

    There are devices called "boost converters" that can step up your voltage. They are used extensively in the small VFDs that accept 120V single phase input and allow you to run a 230V 3 phase motor....
  8. Replies
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    1,245

    TRS jacks are not listed for any kind of load or...

    TRS jacks are not listed for any kind of load or voltage that makes them useful for this, they are for audio equipment only.
  9. Replies
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    1,396

    No. Back in the days before CNC, the back panels...

    No. Back in the days before CNC, the back panels for standard starters like this were all punched for every possible combination of devices that could go inside.
  10. Replies
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    The nice thing about standards is that there are...

    The nice thing about standards is that there are so many different ones to choose from...

    Different countries use different standard symbols. In Europe they are supposedly the same everywhere (IEC...
  11. Replies
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    411

    2. You would have to add an external OL relay...

    2. You would have to add an external OL relay between the VFD and motor, more cost, wring etc.

    3. 1.6A is your motor FLA at 440V 3 phase, but the current at single phase increases at the square...
  12. Replies
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    Before my time but it was still kicking around on...

    Before my time but it was still kicking around on some older literature.
  13. Replies
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    3,580

    I agree with everything except the absoluteness...

    I agree with everything except the absoluteness of getting dinged for poor Power Factor Most utilities in California only ding you for Power Factor as a DEMAND charge, meaning IF you are not using...
  14. Replies
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    411

    1. If you buy old VFDs at auctions, you most...

    1. If you buy old VFDs at auctions, you most likely need to do what is called a "Capacitor Reforming Procedure" BEFORE you apply ANY line power to them the first time, or you might damage the...
  15. Replies
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    1,199

    Anything over the carrier frequency the drive was...

    Anything over the carrier frequency the drive was designed for increases the heating of the VFD, most are designed around 4kHz. Of those responsible enough to include a de-rating chart, 16kHz...
  16. Replies
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    1,396

    A-B 712 starters have been obsolete for decades...

    A-B 712 starters have been obsolete for decades now so part numbers are meaningless, there are no more spare parts. But that’s actually irrelevant. What burned out is the Control Circuit...
  17. Replies
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    1,176

    If you don't understand the references to "Demand...

    If you don't understand the references to "Demand Charges", commercial and industrial users are charged a separate amount for what the Utility must keep in reserve to handle your demands during peak...
  18. Most modern VFDs will work for this by simply...

    Most modern VFDs will work for this by simply doubling the amp rating of the VFD with respect to the motor nameplate amps. So if your 5HP 3 phase motor says it is 15A, buy a VFD that is rated for at...
  19. Replies
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    Why on earth would you buy a compressor from...

    Why on earth would you buy a compressor from China with a 380V 50Hz motor on it? Cheap aint so cheap when it fails...

    But yes, if you step up your 240V 1 phase to 480V 1 phase, then feed a 480V...
  20. Replies
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    Look at the data you posted, I have highlighted...

    Look at the data you posted, I have highlighted the pertinent info for you. It's right in the description of the VFD.

    If the VFD already SAYS it is for single phase input, that means the VFD mfr...
  21. 9100 is right, it's a CURRENT spike on energizing...

    9100 is right, it's a CURRENT spike on energizing a transformer, not a voltage spike, and it will only last a fraction of a second, usually too fast for fuses or circuit breakers to react (but not...
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    Sounds like you have a plan, but to answer your...

    Sounds like you have a plan, but to answer your first question on using a 2HP VFD on a 5HP machine, here is how that works.

    The VFD is rated for an amount of CURRENT it can safely handle. A motor...
  23. Did you measure the voltage under load, or with...

    Did you measure the voltage under load, or with no load on it? Voltage will look high with no load on the RPC, it might look different under load.
  24. Stuttering / jittering at low speed is often a...

    Stuttering / jittering at low speed is often a symptom of the drive being in what's called "Sensorless Vector Control" (SVC) mode, but you did not perform what's called an "autotune" or "Motor ID"...
  25. Thread: C-11G contactor

    by Jraef
    Replies
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    1,306

    That is a Taian brand contactor. Taian is the ...

    That is a Taian brand contactor. Taian is the brand name of components made by Teco (Taiwan Electric Co). They have really poor market access outside of Asia but are actually a fairly big supplier....
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