Hey there,
I have some basic electrical knowledge and since the second out of two halogen bulbs on my range hood blew out, I thought it would be the time to replace those by 3W LED COBs (which are labelled as 12V AC or DC).
The original bulbs are 12V 20W G4 halogen bulbs. Looking at the schematics there's a transformer (of course) between the line feeding 120V AC and the processor board. So 2 wire in, but 3 wire out; one wire is going to 12V Hi-beam, another one going to 9.5V lo-beam, and the third one is neutral.
So, thinking I could do a direct swap, I pulled the old halogen and plugged the LEDs in. I see a flash of light, then nothing. Or so I thought. Taking a look at the bulbs, I could see a very faint light coming out. Pressed the light button again to switch to lo-beam and it got even dimmer. Well, the bulbs are functional. So I took my multimeter, pulled a bulb out a little, and metered at the pins. I had 0.9V....I was puzzled.
Then, reading a bit, I eventually remembered how LEDs suck so little current, and how the transformer inside my hood will most likely require to be replaced by a LED driver...!
First: am I right?
Second: If I am, then I have another question.
Since there is no such thing as a 3-wire output LED driver (that I know of), in order to preserve hi and lo beam function (without jumping the 12V and 9.5V wires and having only hi-beam), could I take:
1-3x1W (output voltage DC 3-11V 300mA) driver hooked up to lo-beam 9.5V considering 2.85W = 9.5V x 0.3A
and a
4-7x1W (output voltage DC 12-25V 300mA) drive hooked up to hi-beam 12V considering the leds draw a total of 6W @ 12V
Both of their neutral wires would be hooked up to the neutral terminal on the processor board (please see attachment). Does this make sense?
I have some basic electrical knowledge and since the second out of two halogen bulbs on my range hood blew out, I thought it would be the time to replace those by 3W LED COBs (which are labelled as 12V AC or DC).
The original bulbs are 12V 20W G4 halogen bulbs. Looking at the schematics there's a transformer (of course) between the line feeding 120V AC and the processor board. So 2 wire in, but 3 wire out; one wire is going to 12V Hi-beam, another one going to 9.5V lo-beam, and the third one is neutral.
So, thinking I could do a direct swap, I pulled the old halogen and plugged the LEDs in. I see a flash of light, then nothing. Or so I thought. Taking a look at the bulbs, I could see a very faint light coming out. Pressed the light button again to switch to lo-beam and it got even dimmer. Well, the bulbs are functional. So I took my multimeter, pulled a bulb out a little, and metered at the pins. I had 0.9V....I was puzzled.
Then, reading a bit, I eventually remembered how LEDs suck so little current, and how the transformer inside my hood will most likely require to be replaced by a LED driver...!
First: am I right?
Second: If I am, then I have another question.
Since there is no such thing as a 3-wire output LED driver (that I know of), in order to preserve hi and lo beam function (without jumping the 12V and 9.5V wires and having only hi-beam), could I take:
1-3x1W (output voltage DC 3-11V 300mA) driver hooked up to lo-beam 9.5V considering 2.85W = 9.5V x 0.3A
and a
4-7x1W (output voltage DC 12-25V 300mA) drive hooked up to hi-beam 12V considering the leds draw a total of 6W @ 12V
Both of their neutral wires would be hooked up to the neutral terminal on the processor board (please see attachment). Does this make sense?
Attachments
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