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  1. hevans1944

    Electronic kart

    If I recall correctly, a world-class manufacturer in Switzerland makes and sells very reliable variable frequency motor drives. Can't seem to recall the name, but we used them for lubricant test stands where a motor ran for weeks at a time, driving a heavily loaded shaft spinning in steel ball...
  2. hevans1944

    Electronic kart

    Back in the last century, around 1980 of thereabouts, I was going to build a go-kart for my two boys, based on two reel motors from a scrapped 9-track computer tape drive. These two reel-drive motors were salvaged from a commercial tape drive. The two huge DC motors were used to move the tape...
  3. hevans1944

    DC motor brush question

    It has always been my observation that it is easier to ask for forgiveness than to ask for permission. Ask away @hotrodjohn71.
  4. hevans1944

    Electronic kart

    If the device accepts 12 V DC and outputs 220 V AC at 3000 watts, it is called an inverter, NOT a transformer. And 3000 watts delivered by 12 V requires 3000 / 12 = 250 A of current from the 12 V battery at 100% inverter efficiency, which is impossible to achieve. The @Audioguru was being...
  5. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    Your latest graphs look like what I would expect on a rainy/cloudy day. It appears there are occasional breaks in the clouds that cause the output to "spike" upward. And the gradual increase in the morning, followed by a gradual decrease in the afternoon, is what i would expect too. It looks...
  6. hevans1944

    Type of sensor for project

    Yes, many times when I was a youth. And would do it again if we ever decide to raise a few chickens here in Florida. Same-o, same-o if my wife decides to raise a few rabbits for meat again. You are overthinking this. There are several ways to slaughter a chicken quickly and cleanly. My maternal...
  7. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    It's almost 8PM here in Venice, FL and nearly dark outside. Sunset occurred here at 7:20 PM, which sort of explains why it is nearly dark outside... Later this evening... In previous posts, I referred to HNI, meaning High Noon Indiana, mistakenly thinking you were in Indiana instead of Kansas...
  8. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    There is no such thing as a dumb measurement. Dumbness creeps in when you wrongly interpret the result of the measurement. And there is no such thing as "real light" versus whatever you think the alternative is. Light just IS and the solar cell array works just fine using incandescent...
  9. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    You mentioned in post #1: So how did you "measure" that the solar cell was producing 1.49V at 70 micro amps? Did you place a load resistor of about 21.3 kΩ across the solar panel terminals, and then measure 1.49 V across that resistor under incandescent room lighting conditions? If so, there...
  10. hevans1944

    DC booster converter strange behaviour

    That is not the way it should work! If the input current for 12 V input is greater than 15 A (causing the fuse to blow) something is seriously wrong. Perhaps the MOSFET switches are shorted. Perhaps the circuit isn't oscillating. Did you accidentally connect power with reverse polarity? This...
  11. hevans1944

    laser ttl module

    Why would you even think this would work? TTL (Transistor-Transistor Logic) levels are limited to a range of zero to +5V. Applying 12V to a TTL module is NOT a good idea. Are you asking because someone has already done this, and now the laser engraver doesn't work? RTFI before messing with...
  12. hevans1944

    Can i plug a 115v power bar to 110v - 240v extension?

    And they almost never provide any indication they have died, leaving you unprotected against power line surges. Not that you should rely on a power bar or outlet strip to do that in the first place. Instead, use a small battery-operated UPS (Uninterruptible Power Supply) that floats the battery...
  13. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    I am impressed that you were able to write code that sent data from your RPi to a URL website address and then display that data as a graph for screen capture. Hmm. Does anyone still write native HTML to build web pages anymore? I thought this sort of thing was now down by "script kiddies" using...
  14. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    @ge96: I am sorry that I misled you in suggesting photo-voltaic output voltage is a function of illumination wavelength. This applies only to photo-electrons emitted from metals in a vacuum. For a silicon PV cell It is a function of the band-gap of the semiconductor materials used to the form...
  15. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    @ge96: To save you some time, go look at this Google results page.
  16. hevans1944

    What is your troubleshooting sequence?

    Making sure the power is right is the most important thing. No point trying to "troubleshoot" if it isn't! I once wasted a whole day in my youth trying to "troubleshoot" a complex analog op-amp circuit (multiple op-amps) before noticing there was no power on the power supply rails. So that's the...
  17. hevans1944

    Reading value from Solar Panel Cell, current peak concern

    Go read the paper that won Albert Einstein his Nobel Prize. Or read about it if you don't read German. Photo-voltaic cells produce a voltage output that is a function only of the wavelength of light to which they are exposed. They produce a current into a load resistance that is a function of...
  18. hevans1944

    SSR triac not releasing

    This is really weird. The SSR should NOT behave the way you describe. Do you have a spare for comparison? Removing and disconnecting the load about three times before the SSR finally releases? Shouldn't happen. Repeat this "test" with the SSR turned "on" but with the control inputs shorted. Can...
  19. hevans1944

    Real Solder

    If you can get it, the so-called eutectic alloy 63% Sn and 37% Pb, is easier to solder with. It has a very narrow range of temperature, approaching zero, where it is neither liquid nor solid. In other words, the liquidus and solidus states occur at the same temperature with no plastic or slushy...
  20. hevans1944

    SSR triac not releasing

    A natural assumption. I didn't even catch the "coil" inside the SSR, which the OP obviously thought was a functional equivalent to what is really going inside a "zero crossing solid state relay" module. I wish "they" would quit calling these things "relays" when "solid state switch" is more...
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