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LED Driver - Luminaire still lights up

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lufer17

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Guys I'm having difficulties regarding a light drive, I'll report the problem and what I did to try to solve this situation.

The light driver is being placed in an LED fixture, when you clear a phase (using interrupted or forcing a phase out), the LED is lit, it stays lit very dimly. And when you touch with your hands or the earth in the structure area of the luminaire (housing) it increases a little over brightness.

Checking the board (light drive), when it eliminates a phase it still manages to release a small amount of voltage with fluctuations (strange and curious).

The following situations that have to be solved: I studied the circuit, unfortunately it is a black box, because the integrated does not have the code that describes the component, so the following methods were used, T filter, I used a coil at the input and output of all people and cores, input capacitor, I used a circuit that isolates the positive or negative output of the drive.

Without much success I appealed to creativity. I bought two MOC 3021 photo couplers on each output, I isolated positive and negative, that way I managed to eliminate the luminosity that shouldn't be there in the absence of a phase, but I turned on the MOC directly and evidently it heated a lot. So I took one and at the MOC output, I connected 2 BT134 to the same form as the MOC previously, to my surprise instead of solving the problem it returned to the initial state of the problem. No heating, but the initial problem returned.

Summary: It works two MOC directly connected but high heating occurs. Another MOC method occurs lighting.

I would like some help regarding the subject.
 

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Hi,

The 85V are DC, maybe pulsed.
But the MOCxxx and a triac are for AC applications only.

Two MOCs in series makes no sense.
Two triacs in series makes no sense.

****
From your explanation there is a good chance that the dim light is caused by leakage currents .... maybe independent of LED_driver circuit.

--> what happens when you connect a 33k resistor in parallel to the LED string?

Klaus
 

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