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  1. Hero999

    Project Help / Advice

    Wow, that looks like a complicated project. Sorry but it's a bit beyond my experience level so don't expect much help from me. Are you using a thermal imaging camera? I imagine that's the best thing to use for detecting fire.
  2. Hero999

    need help creating a simple circuit.

    Not far off, you forgot to say that the power supply needs to be able to provide enough current to the bulbs. In your case, it needs to be able to supply at lease 250mA, note: it can supply more than that; it doesn't matter if the supply is 9V rated to 300mA.
  3. Hero999

    Single PCB Production

    He's got no right to criticise someone else's English when he can't even spell Greece.
  4. Hero999

    Brightest LEDs on the planet?

    Why do you want 8000k? That's blue. If you get a RGB LED you can alter the current to each LED to get any colour you desire.
  5. Hero999

    Single PCB Production

    He's making fun of your spelling, it's  Greece not Grease.
  6. Hero999

    Limiting Mains current.

    You're right that using an isolation transformer would be more expensive and heavier but you've missed an important point: safety. An isolation transformer, disconnects the neutral from the earth, making i so you have to touch both wires to get a shock. As you currently have the circuit...
  7. Hero999

    0-30V Stabilized Power Supply

    Don't forget that the purpose of a fuse if to prevent the cable or transformer from melting adn catching fire down if a fault occurs. In this case there are two things that are most likely to cause this: a shorted turn inside the transformer (hopefully the internal thermal fuse will kick-in)...
  8. Hero999

    Limiting Mains current.

    That's the point I was trying to make with regards to the rectifier. What's the continuous current rating of the rectifier? 1.5A? The chances are it can easilly withstand a 15A surge or more. I have a 100VA isolation transformer, it isn't that heavy, the DC resistance of its secondary winding...
  9. Hero999

    need help creating a simple circuit.

    Parallel is best because it means that if one lamp fails, the rest will continue working and you can safely mix bulbs with different power ratings. Of course you could use a 50V transformer and connect them all in series but you're better off with a 9V/10V transformer and connecting them in...
  10. Hero999

    0-30V Stabilized Power Supply

    I normally put the fuse on the primary side and use a slow blow so the surge current won't be a problem. For 120V operation, I wouldn't use anything less than 1.5A, 3A would be my first choice.
  11. Hero999

    Remove the Sell/Buy electronics - Job offer/requests section?

    I'm not the administrator, my power is limited to a few sections so I couldn't do that even if I wanted to. Spam seems to come in phases, often we don't have any but sometimes the forum becomes filled with it.
  12. Hero999

    Remove the Sell/Buy electronics - Job offer/requests section?

    On second thought may be it doesn't matter if this section gets abused if it diverts spam from other areas? There again, I'm not sure it does, the high voltage section always seems to get most of the spam for some reason, maybe it gets more Google hits than the other sections?
  13. Hero999

    0-30V Stabilized Power Supply

    If a project is low powered <1.5A then it's a good idea to add a fuse because the lowest rating plug fuse you can normally buy is 3A and won't be enough to protect the circuit. Unfortunately most cheap transformers have one shot thermal a one shot, non-replaceable thermal fuse which is why...
  14. Hero999

    need help creating a simple circuit.

    Yes, you're right, the charger doesn't have a high enough voltage and mains voltage is too high so the bulbs will be destroyed. How many bulbs are there? What's their Wattage or current rating? You need a transformer, 9V will probably do.
  15. Hero999

    Anyone here na gumamit na ng RGB LED/White LED for color detection

    Only the first and last sentence make sense, the rest is gibberish. The easiest way is to use three LEDs: red green and blue, and a photo diode. I'll post more information if you're interested.
  16. Hero999

    50V, 50A H-Bridge IC needed

    Those should be fine but you'll need to connect two in parallel for 50A. Looking at the datasheet, the STP40NF10L should be able to pass 25A with a gate voltage of 5V so you shouldn't need any level switching.
  17. Hero999

    Limiting Mains current.

    It's up to you but bear in mind that for 1.5A you'll need a pretty large capacitor which will also require something to limit the current as well as a bleeder resistor. You could use a resistor but you have to live with the power loss. Also note that, in this case, the rectifier's peak current...
  18. Hero999

    Brightest LEDs on the planet?

    Without seeing the fitting it's difficult to say. If one of the reasons for using LEDs is for the efficiency then you're defeating it with a Peltier cooler. CPUs normally use around 100W so a CPU heatsink plus a decent fan should do the job, even then you could use a thermostatic control so...
  19. Hero999

    connect two diff make 24 power supply in parallel.

    It depends on the power supplies. Some power supplies are designed to be paralleled but it normally means setting one as the master and the other as the slave. If you don't know then they probably can't be paralleled and will fight each other as audioguru said. You could try using a Schottky...
  20. Hero999

    0-30V Stabilized Power Supply

    The transformer is not perfect and has an equivalent series resistance which drops the voltage when a current it drawn.
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