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  1. J

    Help me figure out what this is

    well a motor is an inductor, so the easiest way to correct PF is to add in some capacitance. Is that not really what they are doing here?
  2. J

    Exactly how evil are Capacitors?

    could it be a hot topic icon?
  3. J

    Exactly how evil are Capacitors?

    its the follow icon, means you have subscribed to the thread
  4. J

    Exactly how evil are Capacitors?

    dorke makes a good point, here in the states I think the max. voltage for UL listed cat 2 measuring equipment is 600V. Everyone here has stated the obvious, electrocution will kill you! The below video is a stark reminder when someone doesn't pay attention to the rules or doesn't follow proper...
  5. J

    LTSPICE and 3 phase w/ transient analysis - SLOW!!!!!!!!!!!!!!

    I was right in my thinking. I actually came up with 5.5ms but knew that wasn't exactly right because of rounding errors so I took and educated guess and added in the decimal places from the 50Hz numbers posted in that pdf. It was close ;) Anyway, thanks for the clarification/formula and the...
  6. J

    LTSPICE and 3 phase w/ transient analysis - SLOW!!!!!!!!!!!!!!

    I been messing around with LTSPICE lately in an attempt to play around with some 3 phase wiring ideas I had been trying to understand. All was working out well till I tried to simulate a step down isolation transformer according to this pdf file here page 44...
  7. J

    3 phase drum switch wiring -- validation

    The attached photo is the only paperwork I got for the drum switch. There is no form350-21c to be found on the internet and since A&B was sold, Rockwell automation doesn't know squat. But, I have a 3 phase motor. I plan on hooking this up for maintained contact with the following wiring...
  8. J

    I'm serious!

    Those things barely get hot enough to even melt solder, let alone the kind that melts at a higher temperature. Throw it away and spend a few bucks on a 30W iron or something similar.
  9. J

    Solar->Battery->Timer->Water pump

    You would probably need to go into detail a little more about the above load to find the answers to your other questions. if it is a 120V AC pump then I think a 12V solar panel is not going to cut it to say the least.
  10. J

    Where is Electronics Point based?

    http://myip.ms/view/comp_ip/840354178/50.22.201.130
  11. J

    another motor question

    https://www.electronicspoint.com/treadmill-repair-and-pleasing-wife-t47284.html Well well, the answer was here all the time. LOL
  12. J

    another motor question

    Ok, so when I picked up this motor it came with a SCR speed control circuitry. I managed to wrap my head around it and wired it up for the most part and got the motor working with the controller. But, I have one left over part! I believe it is an inductor and I am just wondering on what side of...
  13. J

    recommend a multimeter

    Just as the title says. I had a decent sears multimeter from 20 years ago and it worked great for years. But good things never last a lifetime it seems. Calibration seems to went wonky with it and I am getting all kinds of wacky readings. Clearly it is more price effective to buy a new meter...
  14. J

    another motor question

    What does that mean for the ratings on the nameplate then? Under what condition is that measured?
  15. J

    another motor question

    I managed to grab an industrial 1.5 HP baldor DC motor for the right price out of luck today. I am trying to understand one important thing. How voltage and current relate to the motor. From what research I have done to my limited understanding. Voltage controls the speed of the motor. The...
  16. J

    Universal motor bi-direction speed control

    Well I hooked the motor up to my 12VDC bench supply and it turned the motor at a rather slow rpm. Hooked it up to the 5VDC rail and it turned even slower. This gives me plenty of options to power the motor. The simplest being a Variac, I bought one for $10 dollars at the flea last summer.
  17. J

    Universal motor bi-direction speed control

    yes mains voltage of 115 volt so says the name plate. It also says it is DC. I know you can run these on AC or DC. Would it make more sense to rectify mains and use a big MOSFET and PWM to control the speed? Max RPM is listed at 16.5k. I need to be at about 10 - 20% of that speed. But I have a...
  18. J

    Universal motor bi-direction speed control

    did a little research since you chimed in. A dimmer switch would work in this application as I am only looking at 840 watts. I do however think I will be well under that rating as I don;t plan on running this motor at anything less then 20% of it's rated rpm. Still need to figure that out. I...
  19. J

    Universal motor bi-direction speed control

    I found a universal motor. I know these can be used on either AC or DC and to reverse the direction all one needs to do is reverse the polarity of the field coils compared to the communicator? Now what about speed control, I have read that you can use a triac to act as a speed control for a...
  20. J

    solution to soft start an ac induction motor

    I had the same thought using a resistor. I was really hoping they made something like a soft start capacitor, but as you say changing direction causes an issue because it would work in one direction and be totally negated in the opposite direction. Oh well, seems I might have to bide my time...
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