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  1. sunnysky

    Pulse generation

    Do you still need a solution? 480W custom $2/W is not unreasonable. What load type is this Resistive, Capacitive or ? With a 80/6 ~13 ohm load a 6,000 uF cap will discharge in 13*6m= 48 ms where it decays 63%. NG.
  2. sunnysky

    Elevator Controller SCCRs

    https://www.se.com/ca/en/faqs/FA87350/
  3. sunnysky

    Need a camera for OCR

    Any smartphone with a 4k cam can do OCR using Google translator if you can find a used one cheap enough.
  4. sunnysky

    36V step down to 12V/20A for two pairs of LED’s

    > this is a 63 Ah battery and I am burning 4 x 10A LED, does that mean this thing will only run for an hour and a half? DC 36V/48V Step Down to 12V 20A 240W DC DC No. But it does mean one 12Vout converter can only power 2 Lamps A total power of 480W out load might need 530W input or so to...
  5. sunnysky

    36V step down to 12V/20A for two pairs of LED’s

    You should link the LED luminaire specs, because chances are it has a DC-DC regulator built in already which may present other options.
  6. sunnysky

    Power Transformer - IP (Ingress Protection)

    It would be redundant to specify IP but they would be IP66 as dust and pressurized waterproof. They would fail DGA early in life if not.
  7. sunnysky

    How to check insulation of a field of electrostatic precipitator?

    https://en.wikipedia.org/wiki/Electrostatic_precipitator#Collection_efficiency_(R)
  8. sunnysky

    Power Flow Analysis for Industrial Facility

    BC Hydro had some suggestions Here are some of the first things you should check for low p.f. - Check if you have any rack-mounted film caps rated for xx kVARs - Large fans and motors only partially loaded have low pf. - Equipment with a high number of transformers (such as lighting ballasts)...
  9. sunnysky

    Effects of brownouts and power spikes on linear power supplies

    We can only guess unless you tell use the model (link to specs and your brown-out levels and qualification test results. You cannot guess without testing them.
  10. sunnysky

    Circuit/components to "help" battery through spikes in current draw

    The max current of 4A is quite low for high-quality batteries. This limits the I^2R=P power dissipate and R is the sum of each cell ESR or Rs which rises rapidly below 10% charge (SoC). The power capacity W=VI and voltage drop at max load depend on the above parameters. Battery cells are like...
  11. sunnysky

    AC CONDENSER FAN full speed continually 199% DUTY CYCLE

    199% would be an overflow measurement possibly with no cycles and just DC full ON.
  12. sunnysky

    Understanding complex input and output in frequency response FEA

    All mechanical structures will have at least one resonant frequency in each axis depending. The stiffness must raise the frequency to limit the displacement that has a 2nd order attenuation with rising frequency. The acceleration transfer function can be defined by the classic 2nd order equation...
  13. sunnysky

    VFD Shaking Loads and Regenerative Braking

    https://instrumentationtools.com/dc-injection-braking-in-vfd/
  14. sunnysky

    Reading lamp

    The best light intensity depends on the background light intensity as the eye pupils adjust to the field of view. So there is no fixed optimum intensity is just enough to minimize eye strain from being too dark or too bright. My estimate is that the contrast ratio or SNR of reflectance for...
  15. sunnysky

    Difference between HV and LV output LLC converter?

    There is an obvious difference in the rated load impedance, which determines the ZL(f) and Zc)f) impedances which may affect cost, Q and type of components, effects of parasitics and creepage on the layout to maintain the same thermal and dielectric breakdown margins. Rated Load ===========...
  16. sunnysky

    neuroscientist needs advise on PC based probe monitoring

    You have not given very detailed specs, but the solution could be simple if you did, or much more complicated if you don't have any design skills. This is just a digital tachometer. THere are lots of solutions used for other things that can be adapted for your needs. To use something industry...
  17. sunnysky

    New Interchange?

    I think I'll try the bike path ;) I'd like a word with the York and Toronto traffic light engineers about the congestion and low traffic flow from ineffective timing. Especially after 2 lanes were lost for Viva bus lanes. It is ridiculous.
  18. sunnysky

    Testing equipment for measuring powerline ground impedance

    I can't imagine a better tool for flashover impedance measurements using ground references approx 100 m in either direction to measure voltage and current from a safely induced spike to the tower. (unless it also measured PD (partial Discharge) the precursor to corona, hint hint) I wonder...
  19. sunnysky

    secondary fuses blow when shutting down

    The aging master switch may be arcing during shutoff and should be inspected for voltage drop when running or signs of wear. Flashover with stored kinetic energy ought to be snubbed with an RC film filter.
  20. sunnysky

    Does phase sequence/ phase shift in input AC supply affect rectified DC output ?

    From the web, an example of a "fully controlled rectifier." is a new name for an old design of any multiple independent isolated Triacs with a shared controller and a shared ZCS. I did an 8 channel version of this back in the late '70's. Q.1 Does phase sequence/ phase shift in input AC supply...
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