Search results

  1. V

    Electro Magnetic field biological effects - AC vs DC, current vs voltage?

    When considering electro-magnetic fields emitted by very close heating devices (for example electric blankets/foot warmers etc. etc.) which type of power would produces the least harmful effects. What are the various biological effects (or possible effects) of voltage vs current and dc vs ac...
  2. V

    Are deep red 660nm LEDS completely safe?

    If you light a room with 660nm deep red that feels comfortable and doesn't seem too bright and you are not looking at the leds except for the occasional glance perhaps, would you expect any hidden dangers to be present?
  3. V

    Best wall power supply for automotive 12v 1w ioniser module

    Ok thanks It's just that I have no way to actually test it, so if it was broken by too high a voltage I probably wouldn't know (apart from counting the dust particles in my projector beam). One of the higher current plug packs I tested started at 17.something volts. In an electronics book I am...
  4. V

    Best wall power supply for automotive 12v 1w ioniser module

    Power requirements: DC 12V Power use: <1W So if I need a 12v power supply with .083 amps. But I only have a plug pack that supplies 150mA, would I need a resistor? Since with plug packs the voltage starts off higher than 12v but goes down under load. It is designed to be used in a car with a...
  5. V

    Are deep red 660nm LEDS completely safe?

    Thanks. They appear to generate less lumens for a certain amount of power, is this because they are less efficient or because the lumen ratio is based on sensitivity to certain frequencies? Would it be safe to replace a safe amount of white led lighting with 660nm deep red leds of equal power...
  6. V

    Are there any dangers associated with ceramic coated reptile heating bulbs?

    Are there any dangers with ceramic coated reptile heating bulbs when placed overhead as a heat lamp? What is the exact frequency that the ceramic coating is converting the light into, is this a dangerous wavelength for your eyes? Does the fact that it is diffused over the whole ceramic coating...
  7. V

    Are deep red 660nm LEDS completely safe?

    I just want to light a room with a colour effect, I just wanted to know if there are any dangers with that particular colour/wavelength (660nm) of leds compared to white leds. With a similar number of lumens you would use to light the same room with white leds.
  8. V

    Are deep red 660nm LEDS completely safe?

    Sorry I should rephrase that, are there any hidden dangers? Is it safe to say that if it too bright to look at you will automatically look away in a room lighting application.
  9. V

    Are deep red 660nm LEDS completely safe?

    Having learned about the dangers of IR leds even from a distance. I wanted to know if visible light deep red 660nm LEDs are completely safe?
  10. V

    Safe distance to look at a 950mn 5w Infrared LED from?

    Look at briefly, I had thought of using it for either an enclosed box heat lamp for heating things (like sprouts in winter), or a ceiling heat lamp for near infrared, like the incandescent heat bulbs, but it doesn't sound safe to use as a ceiling heat lamp if you can damage your eyes just from...
  11. V

    Safe distance to look at a 950mn 5w Infrared LED from?

    Thanks, wow 5 metres it's quite powerful then. Also would there be a simple way to diffuse the beam a lot so there is no strong point source (by mounting something infront of it)? Or would an array of lots of very low powered ir leds be safe? Is there something I can put in front of it to...
  12. V

    LED driver for my LED

    Ok thanks, yeah I think I'll leave it now since it's working and I glued it to a board etc.
  13. V

    Safe distance to look at a 950mn 5w Infrared LED from?

    So the beam width is just defined by the leds, the module is not lensed or lasered outside of the actual leds themselves.
  14. V

    LED driver for my LED

    What would happen if I connected it to a 2a supply to try and get 10 watts?
  15. V

    Safe distance to look at a 950mn 5w Infrared LED from?

    Lol It's one of these http://www.ebay.com.au/itm/231097780060?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT It doesn't say the beam width, but maybe someone could make a guess by looking at the photo. It says 10w but it's running at 4.25v x 850mA with my driver.
  16. V

    Safe distance to look at a 950mn 5w Infrared LED from?

    Can someone give me a guide or make a estimation of what is a safe/unsafe distance to look at a 940nm 4.3w Infrared LED?
  17. V

    LED driver for my LED

    I connected it to the 850mA led driver and when looking through the digital camera (using the lcd screen display) there is a slight (I think blue) glow through the camera lcd. Is that expected? When I connect a multimetre across the terminals while it is running it detects 4.25v Does that...
  18. V

    LED driver for my LED

    Ok thanks, yes I know that it will be bright even though not visible, I will point it away when testing. When I test it with the 850mA led driver I guess I'll have to use a thermometre to see if it is working or not since the light probably would not be visible at all. I hope I can determine...
  19. V

    LED driver for my LED

    Ok thanks. Do you think that led is actually 1a 10v 10w or 1a 5v 5w? If I use a plug pack power supply, how much headroom should I have for driver inefficiencies above the 5w of the actual led? Someone said that my 4.5v 1a plug pack could drive the led with no resistor, would this be right...
  20. V

    LED driver for my LED

    Ok thanks, that answered my main question well. But do you think that the 1a LED could be driven with a 850mA driver and it would run at a lower brightness or would it be too low considering the curve with LEDs and barely light up or not at all? Also if I was to buy a new driver that was...
Top