Yep. But some say a 12v transformer will do and others say not.
LED flicker
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A real transformer will do, BUT for the SEVENTH time a SMPS designed for halogen lights will not.
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Earlier today I did some experiments with MR16 size LEDs on a SMPS. With enough of them and a halogen lamp in parallel I got them to light up. But they ran very hot and the power draw was about double their rated power. I then tried them on a real transformer and they worked without the above problems. I guess they didn't like a 30kHz square wave and would have had a short life. They were actually quoted as being 50/60 Hz AC or DC, and came with a warning in the box about running them on unsuitable SMPS.
So, they will therefore run on suitable SMPS
you won't have a problem posting a picture of this warning then.
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A suitable will be a DC power supply, not one that runs at 30kHz. Picture can be made available but not this time of night. Don't you believe me then?
https://www.osram.com/osram_com/pro...-reflector-lamps/led-star-mr16-12-v/index.jsp
Just one lamp chose at random, looking at the compatibility chart tests prove works with over 90% of Electronic Transformers, even ones with a higher minimum load than the actual lamp
Just one lamp chose at random, looking at the compatibility chart tests prove works with over 90% of Electronic Transformers, even ones with a higher minimum load than the actual lamp
Technical dataExpand
Electrical data
Rated wattage 4.50 W
Nominal wattage 5.00 W
Nominal voltage 12.0 V
Claimed equiv. conventional lamp power 35 W
Operating frequency 50…60 Hz
Power factor λ › 0.60
It clearly says "electric transformer" compatibility, nothing about your so called "electronic transformers". It also says OPERATING FREQUENCY 50...60 Hz.
So definitely NOT compatible with SMPS at 30 kHz odd.
The secondary is rated at 11.6 V~ rms rms = Root Mean Square
The rms of a 40,000 Hz Square wave 23.2 volts chopped at 50/50 ratio can be said to have an rns value of 11.6 volts
Feeding an LED driver with 40,000 Hz may work, it may not, it may make the LED driver so unstable in operation that damage to driver and/or LED elements occurs.
The rms of a 40,000 Hz Square wave 23.2 volts chopped at 50/50 ratio can be said to have an rns value of 11.6 volts
Feeding an LED driver with 40,000 Hz may work, it may not, it may make the LED driver so unstable in operation that damage to driver and/or LED elements occurs.
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That's not how they usually look though. Almost all electronic transformers for halogen lamps have a 50Hz sinewave modulated onto a >20kHz carrier frequency. As far as the 12V LED lamps are concerned, it's a 50Hz sinewave. I've never seen a 12V LED lamp without a bridge rectifier and reasonably sized capacitor after it, which would filter the carrier frequency out.
For a modulated carrier at 100% modulation 2/3 of the power is in the carrier and 1/3 in the modulation. If the LEDs only see the 50Hz (which I doubt is actually the case) what happens to the carrier power? Well I believe it goes to heating the LEDs which would explain what I found in my experiments above, post 33.
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