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I am having some trouble understanding what I am observing with some light strip kits I ordered.
Supposedly in the kits I received 12V - 5A power supply, a controller that supports 2A per channel (4 channels), and a RGBW LED light strip. I bought a few of these kits. I was connecting them up to a kill-a-watt meter to try to determine if for our use we connect 2 in series and have the lighting be adequate. When connecting them in series, the lights do start to dim near the end of the run as I expected, however, what is not making sense to me is that for some reason the overall power draw across both strips is lower than the draw across a single strip and I cannot understand why especially since the first strip does not noticeably decrease in brightness when the second is connected.
The strip is wired with 3 RGB LEDS and 3 White LEDS per section. Given that the strips are only 12V strips, I am assuming that the RGB LEDs and White LEDs are series connected independently of each other in each "section". In other words, white->white->white in series is parallel to the RGB->RGB->RGB in series otherwise I do not think there would be enough voltage for all 6 LEDS in series. In each section, I see resistors for Red labeled 331Ohm, Green 151 Ohm, and Blue 151 Ohm. Also, there are 2 resistors labeled "W" which I imagine are for the white channel that are 160 and 340 Ohms.
On the kill-a-watt meter, with 1 strip lit as I intend to use them, I am getting around 32W. When I connect a second strip, the draw DROPS to 26W and this is what doesn't make sense to me. My guess is that the controller current is limited on one of the channels since the power supply is obviously not maxed out, but I am having doubts on that, because I would expect the current drawer to remain close to constant if that was the case instead of the current draw dropping. With the LEDs wired in parallel, I would anticipate the total resistance of the combined strip to drop in half, thus doubling current draw in IDEAL analysis. With wire resistance added do to the length addition, I figured worst case scenario, the net resistance would be the same.
Can anyone shed some light on what is happening with the math behind it?
Supposedly in the kits I received 12V - 5A power supply, a controller that supports 2A per channel (4 channels), and a RGBW LED light strip. I bought a few of these kits. I was connecting them up to a kill-a-watt meter to try to determine if for our use we connect 2 in series and have the lighting be adequate. When connecting them in series, the lights do start to dim near the end of the run as I expected, however, what is not making sense to me is that for some reason the overall power draw across both strips is lower than the draw across a single strip and I cannot understand why especially since the first strip does not noticeably decrease in brightness when the second is connected.
The strip is wired with 3 RGB LEDS and 3 White LEDS per section. Given that the strips are only 12V strips, I am assuming that the RGB LEDs and White LEDs are series connected independently of each other in each "section". In other words, white->white->white in series is parallel to the RGB->RGB->RGB in series otherwise I do not think there would be enough voltage for all 6 LEDS in series. In each section, I see resistors for Red labeled 331Ohm, Green 151 Ohm, and Blue 151 Ohm. Also, there are 2 resistors labeled "W" which I imagine are for the white channel that are 160 and 340 Ohms.
On the kill-a-watt meter, with 1 strip lit as I intend to use them, I am getting around 32W. When I connect a second strip, the draw DROPS to 26W and this is what doesn't make sense to me. My guess is that the controller current is limited on one of the channels since the power supply is obviously not maxed out, but I am having doubts on that, because I would expect the current drawer to remain close to constant if that was the case instead of the current draw dropping. With the LEDs wired in parallel, I would anticipate the total resistance of the combined strip to drop in half, thus doubling current draw in IDEAL analysis. With wire resistance added do to the length addition, I figured worst case scenario, the net resistance would be the same.
Can anyone shed some light on what is happening with the math behind it?
