Search results

Search Forums New Posts
  1. dorke

    5Volts Signal to 60V

    No! This will not work since the PNP will always be on with both outputs of the IC(0 or 5v). Use an NPN with inversion of the signal by the IC(if possible) like @Gryd3 suggested . Edit: A base resistor is needed in both NPN and PNP cases. and you need to calculate both resistors.
  2. dorke

    Optocoupler delay off MOSFET solenoid

    O.K replace the "5V-signal" with this circuit: Inverters are schmidt-triggers (one 74HC14). One silicon-Diode. Tdelay is set by R-C .
  3. dorke

    5Volts Signal to 60V

    o.k. So you wont to have the same 0-5V signal at a larger amplitude 0-60V. and you already have a 60V DC voltage. That is called "level translation" You do need to know what is the load and the frequency/rise/fall time of the 60V signal and current.. a simple general solution :
  4. dorke

    Optocoupler delay off MOSFET solenoid

    I would move the delay to be on the "5v-signal side". If I understand correctly you need the delay only on the shutter-on to shutter-off transition,the other way there should be no delay at all.
  5. dorke

    RF Energy Harvesting Banking

    Here is another paper on energy harvesting in the RFID field.
  6. dorke

    Optocoupler delay off MOSFET solenoid

    "The problem is 5v line have bit fast interruptions on a laser show" What do you mean by "fast-interruptions"? What is creating the "5V signal"? and another thing, why do you need a relay to switch the laser?
  7. dorke

    5Volts Signal to 60V

    What "signal"? What is the current you need?
  8. dorke

    Which Resistor

    Yes it is simple. For the LEDs you have IF=20mA. Vf max= 2.5V Vf Typ(red)=2V Vf Typ(green)=2.2V Since the resistor is common for both LEDs, lets "aim" at 2V: R=[9-2]/20mA=350 ohm R=360 ohm (standard value).
  9. dorke

    Killing SSR (relays) - Need to understand

    Measure at the AC leads coming out of the SSR. You actually need to see all the current that the SSR is "carrying". The one you posted the link to has a Max reading which is a great thing in this case use it as well. Like so: 1. Connect the clamp and turn one the meter in 200/400A MAX mode. 2...
  10. dorke

    Physics

    You did fine. Vi=initial speed g=-9.8m/s^2 (gravity) V(t)=Vi+g*t at the top of the trajectory V(t)=0 ,thus 0=Vi+g*t ,so t=-Vi/(-g) = Vi/9.8 t(TOP)=49 /9.8=5sec (time to the top) The total time of flight is T(Tot)= 2*t(TOP)=10sec
  11. dorke

    Should I design my PSU for 230Vac/+-10%?

    There is a standard called IEC60038 you can find the 6.2 version here there is a newer one 7.0 , and they plan to have another in 2018... You have the US and others with the 110/120V 60Hz and Japan with 100V... For safety you also need to have: For EU the EC. For the US the UL. For Canada the...
  12. dorke

    Killing SSR (relays) - Need to understand

    You need to measure the current Through the heating element. You are correct about your DMM- they usually up to 10A. Like minder said, you need a high current(100A and above)clamp-on like here There are many to choose from. The professional,good and safe ones, are not cheap. There is a way to...
  13. dorke

    Should I design my PSU for 230Vac/+-10%?

    Not a lot of questions at all.;) That's life with "standards", you have to meet them, nothing to do about it. Use a larger filter cap for the 207V case, and a larger heatsink for the 250V case. But, tell us please, Why do you intended to build (and sell?) a linear 2A P.S? I mean, there are so...
  14. dorke

    Camera Power Help

    Welcome to EP. "What connects to the BATT/XEXT input?? " It looks like this is an "external adapter presence indication" input pin coming from the adapter (it is a 3-pin connector). "I believe the ACV is referring to the AC Adapter voltage, correct?" Yes,non-consistent name selection: DC-in...
  15. dorke

    Help needed to replace a relay

    You can get a quote of that exact relay, by it's part number BW240A2-040 here
  16. dorke

    Clean square waves using a 555 timer?

    What is the frequency range of the square wave you are after?
  17. dorke

    Clean square waves using a 555 timer?

    How did you build it? Please post a good photo of the actual build. I would place a good quality ceramic 0.1uF cap between pins 1 and 8, with shortest leads possible. and change the "large electrolytic" to be a tantalum 10uF, again between pins 1 and 8,with shortest leads possible. Is there...
  18. dorke

    Help me design circuit with PID temperature controller for temperatures 150-250 degrees

    Look here and here seems much easier with liquids...
  19. dorke

    Gate driver datasheet for IGBT

    Hi Jeroen, I think more information is needed about your "Turbine"/generator. What is it ?How is the operated?what drives it? What are it's Voltage/frequency/current ratings? Any control of them automatic/manual? What is the purpose of the C7 cap? About TRIACs, Well they are intended for the...
  20. dorke

    Gate driver datasheet for IGBT

    If I understand correctly , you are trying to modify the load of an AC generator(220V RMS) using PWM. The load goes from 0 to 5KW. If so, I would drastically change the solution to be: A 400V/25A TRIAC driven by a zero-crossing opto-triac as the driver. It will simplify everything,be...
Top