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  1. Normal? What's that? Yes, some people did...

    Normal? What's that?

    Yes, some people did that / do that. You lose about 1/2 of the motor's capacity in the process but for some small machine applications, it makes sense to just start with a 3...
  2. 7-1/2HP 230V single phase would be about 40A FLC,...

    7-1/2HP 230V single phase would be about 40A FLC, so starting current could be up to 240A. What size is his service drop from the utility? If it's a residential / light commercial 100A 1 phase...
  3. Thread: Contact cleaning

    by Jraef
    Replies
    40
    Views
    1,598

    From an engineering standpoint there are valid...

    From an engineering standpoint there are valid reasons not to sand or file contacts, the first three of which are what JST brought up. The other big issue is that what some people see as "pitting" is...
  4. Replies
    5
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    460

    Yes. That's a common distribution format. it...

    Yes. That's a common distribution format. it allows for small manufacturing businesses to have a limited amount of 120V loads for lights, office equipment etc., but the MAIN power is intended to be...
  5. It would also be at 1/2 the rated capacity.

    It would also be at 1/2 the rated capacity.
  6. Typically if the motor is designed for "dual...

    Typically if the motor is designed for "dual voltage", it will say so on the nameplate, i.e. 240V Delta, 420V star. You said it "currently in Wye but can be changed to Delta.". Does that mean the...
  7. TLDR: Agree on the nonsensical nature of the...

    TLDR: Agree on the nonsensical nature of the original assertion.

    Energy = work across time.
    At 5/6 motor speed, less total revolutions means less work is performed in the same amount of time. ...
  8. Did you perform the Auto tune procedure? The...

    Did you perform the Auto tune procedure? The symptoms you describe are typical for that. If not, you must do that. Parameter 02-07
  9. About 10 years ago (maybe more), UL changed to...

    About 10 years ago (maybe more), UL changed to require "switching duty" on all UL489 listed breakers, whether they say it on the label or not. Many manufacturers still show the "SWD" on the label out...
  10. Replies
    8
    Views
    993

    Motors create their rated torque based on their...

    Motors create their rated torque based on their design ratio between voltage and frequency (V/Hz ratio) and are generally fine for anything within 10%. Outside of that +-10% window, running torque...
  11. Replies
    2
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    414

    That is a Motorized Potentiometer or MOP. Think...

    That is a Motorized Potentiometer or MOP. Think of a large dimmer (the old kind) but instead of a knob to move the wiper and change the resistance, there is a tiny little gear motor that does it. So...
  12. Yest that is true. It used to be more common that...

    Yest that is true. It used to be more common that it is now, most of the VFD mfrs realized that not giving users the ability to disable the phase loss trip (or ignore phase loss altogether and just...
  13. Replies
    6
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    635

    I think maybe you are thinking of Dynamic Braking...

    I think maybe you are thinking of Dynamic Braking in meaning that the motor must move to have any braking. DC injection braking is different and will indeed "lock" the motor shaft, to a fashion. With...
  14. Not one size up, you need to at least DOUBLE the...

    Not one size up, you need to at least DOUBLE the size of the VFD if feeding it with single phase. So for a 7-1/2HP motor, you need a 15HP VFD. $600 is doable for that though.

    Teco and Hitachi are...
  15. Replies
    8
    Views
    624

    15A breaker cannot be right for the 1-1/2HP if...

    15A breaker cannot be right for the 1-1/2HP if the input is 115V. Remember, the OUTPUT current is not the same as the input current on a VFD, especially one that is converting single phase to 3...
  16. Thread: delta EL VFD

    by Jraef
    Replies
    5
    Views
    527

    VFDs have to be programmed. If you got it used,...

    VFDs have to be programmed. If you got it used, the first thing you need to do is to reset everything back to the factory defaults because you don’t know what the previous owner had programmed it to...
  17. Replies
    25
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    15,408

    Well maybe the axe I am grinding about Schneider...

    Well maybe the axe I am grinding about Schneider is still on the wheel. I worked for Square D right before Schneider bought them and was laid off in a massive sweep as they decided to make most of...
  18. Thread: Vintage VFD?

    by Jraef
    Replies
    29
    Views
    2,359

    Wow, I haven't seen that word in print in a...

    Wow, I haven't seen that word in print in a decade or more... The last time I used it myself was probably 20+ years ago when I was explaining (to a pup) my use of the word "thyristor" as a generic...
  19. Replies
    25
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    15,408

    Not US made, not even a US company. Schneider is...

    Not US made, not even a US company. Schneider is French and although their larger drives sold in North America are built at a Toshiba plant in Texas, the small inexpensive versions of their drives...
  20. The manual is showing you that IF you need to use...

    The manual is showing you that IF you need to use a contactor, it should be on the line side, not the load side*. Some machine safety regulations require that the VFD be automatically disconnected...
  21. Replies
    5
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    470

    Although not official, this site is based in...

    Although not official, this site is based in North America, so the term RCCB means nothing to most people here. We use the term “Ground Fault Protection” and we have two main “Classes” of it, Class A...
  22. +1 on getting rid of the contactor and overload...

    +1 on getting rid of the contactor and overload relay. First off, if it’s a bi-metal OL, it’s a known issue that the bi-metal strips heat up from the harmonics and nuisance trip meaning they trip at...
  23. Thread: Vintage VFD?

    by Jraef
    Replies
    29
    Views
    2,359

    How long had it been sitting around without being...

    How long had it been sitting around without being powered? If you don't know, capacitors go bad if not kept powered up, a process called "deforming". If un-powered for more than a year, you will need...
  24. Replies
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    14,734

    Just a word on forum etiquette: tagging onto a 5...

    Just a word on forum etiquette: tagging onto a 5 year old thread is a great way to get ignored... You should start a new thread with a new issue, reference the old thread if you see relevance.

    If...
  25. Replies
    10
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    705

    If you had a VFD with a "3rd output terminal",...

    If you had a VFD with a "3rd output terminal", you did not have a true single phase output VFD, you had a 3 phase output VFD and someone told you it would work on a single phase PSC motor. It would,...
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