The current going to the LED strip does not pass through the electronics of the digital LED strip controllers (they are connected in parallel). As a result, there is no performance limit in the same sense as with an analog RGB controller, where the manufacturer specifies the maximum current output of the controller, which cannot be exceeded without adding a signal amplifier. In the case of DRGB, such a limit does not exist; at most, the cross-sections of the wires soldered to the controller can be limiting factors. But this can easily be circumvented in the case of digital running lights due to the parallel connection, as it is enough to power the strips, and the controller will also get power from the strip itself, thus the wire cross-section of the controller won’t matter, since only the current necessary for the operation of the controller will load it.
If we only look at the two sets shown in the picture above. It is completely illogical that the right set, operating 150 LEDs on a 5-meter roll in full white light mode, has almost twice the consumption as the left one, which operates 300 LEDs. In contrast, in colorful running light mode, the consumption is proportional to the number of LEDs, but surprisingly, the left one can boost in white light, while the right one falls short as expected. WHAT IS THIS ANOMALY?
Background:
- When a new product arrives in the webshop, I try to test them and write about my experiences. Firstly, I know I cannot believe everything manufacturers write, and secondly, the more complex a product is, the less information they provide.
- When the LEDmaster DRGB 60LED/m (20px) Indoor LED Strip 12V 5 meters (FOR CONTRACTORS) JST-SM-Female and the LEDmaster Digital RGB LED Strip Controller – RF 28 button remote control + Bluetooth + music sensor (5-24V) + button cell + 2xJST-SM-Male arrived, the opportunity presented itself to connect and test them.
- Yes, powering 5 meters from one end, although we know that in such cases we almost always fall short of the performance indicated on the strip.
- It also seems quite logical that if all LEDs light up white, i.e., we set the controller to fixed white light and maximum brightness, then the consumption and luminous flux are the highest. Since all LEDs are on, and all three colors are lit in each LED. Okay, from analog RGB LED strip control, we know that when controllers mix multiple colors, they naturally reduce the power because they want to moderate the flicker of brightness during color changes. A shade of pink cannot be twice as strong as just blue or red. The same applies to white. But no matter how controllers manipulate the maximum luminous flux, we can be sure that we can achieve maximum consumption when we light up white, even if this falls short compared to the version without a controller.
- Naively, I believed that this was also the case with digital RGB because it had been so far.
- I took the LED strip and controller linked above, set it up, adjusted it to maximum brightness and fixed white light, and expected a value close to 50 Watts. To my astonishment, the consumption came out to 17.3 Watts including the power supply. Correcting for the 87% efficiency of the power supply, it was even worse, yielding 15 Watts. Despite the circuit strip being adequately thick and not skimping on the number of LEDs (as it is equipped with the expected maximum of 60 LEDs per meter), powering the other end of the 5-meter strip resulted in 18.7 Watts, or 16.3 Watts without the power supply. It is clear that even if I increased the power connection points to one per meter, I would still only reach a maximum of 25 Watts, which is half of the nominal value. Despite the promising design, it became quite suspicious in my eyes.
- I concluded it was substandard because an older 30 LEDs per meter, nominally 35 Watt consumption LED strip, operated with an earlier DRGB controller, measured 32.2 Watts with the power supply. Correcting for the 87% efficiency of the power supply, it yielded 28 Watts. That is, with half as many LEDs, it has almost twice the power. So, this Optonica LED strip has almost four times the performance per LED.
… then came the realization
Contrary to logic, this LEDmaster RF 28-button remote control Digital RGB LED strip controller has its highest consumption not in fixed white light mode, but when playing a rainbow running light. In this mode, the previously measured power without the power supply jumps from 15 Watts to 17.5 Watts. This 16.66% increase is still low, but if we measure the previously used reference Optonica 5 meter 150 LED running light DRGB LED strip + SP511E IR remote control combo, which was 28 Watts in fixed white light, it drops to 10.9 Watts when playing a rainbow running light, a 61% decrease. Although the two rainbow running lights seem similar in appearance, I tried to find a running light effect on both controllers where all LEDs are always on and change rainbow-like. Thus, per LED, 0.29 Watts versus 0.36 Watts, Optonica still leads, but this difference can now be explained by the differences between the controllers, and it becomes clear that the problem is not with the LEDmaster DRGB 60LED/m (20px) indoor LED strip, but with the controller being the odd one out. This controller was programmed to reduce power in fixed light mode and be strong in running light mode. Perhaps the intention was to ensure that the luminous flux in fixed white light was not stronger than in a colorful running light, but this intention was “slightly” overdone.
To properly compare the two strips, the same controller must be used to avoid surprises and misjudgments.
Let’s see how the two strips perform when the controllers are swapped.
In the picture below, we tested the LEDmaster DRGB 60LED/m (20px) indoor LED strip roll with both controllers. It is clearly visible that if the strip is the same and the two controllers produce different consumption data, the controllers alone are responsible for the consumption differences.
In the following image, we performed the same measurement with the Optonica DRGB 30LED/m (10px) indoor LED strip roll, and the results were approximately the same. Although the two controllers have other different properties, it is clear that the LEDmaster RF remote + Bluetooth controller shines significantly weaker with fixed white light, with the same LED strip, compared to the (white) SP511E infrared remote + WiFi controller. Surprisingly, in a rainbow running light mode, where logically, only 1 or 2 of the 3 primary colors light up per LED, so we would expect half or one-third the consumption, the (white) SP511E works correctly according to this logic, whereas the (black) LEDmaster controller shines stronger in this mode, not only stronger than its fixed white light state but also stronger than the (white) running light performance.
The two figures not only highlight the differences between the two controllers but also the differences between the two LED strips. While the manufacturer-specified nominal consumption for the LEDmaster 5-meter roll with 60 LEDs per meter is 50 Watts, i.e., 10 Watts per meter, the Optonica 5-meter roll with 30 LEDs per meter has a nominal consumption of 35 Watts, i.e., 7 Watts per meter. It can be observed that the LEDmaster strip falls significantly short of this value, even if we only consider the highest consumption measured with the SP511E in fixed white mode. Averaging the 2×4 values gives an 11% performance advantage, but this value is nowhere near the fact that the LEDs are twice as dense and the manufacturer’s nominal consumption promises a 42% advantage.
However, it is an undeniable fact that a twice denser LED strip provides a more beautiful visual effect, and since the LEDs on both strips run in groups of three, the running light effect can offer a twice richer experience.
Considering all these points, if we think in terms of shorter strips, or in larger systems we are not deterred by the creation of more frequent power connection points, then the LEDmaster strip is ideal. However, in the construction of larger systems, the advantage of easier implementation (fewer power connection points) is shown with Optonica. Although the luminous flux is slightly lower, in larger systems with higher consumption, this can even be desirable if energy savings are also considered. But this belongs to the next table.
Consumption values of different lengths and types of DRGB systems
Continuing the thought process from the previous paragraph, I will extract parts from the table below. When installing a running light system, we generally install it so that the light runs. In this regard, the black controller, the LEDmaster, is the winner. Consider a room, say 3.6 meters wide and 6.4 meters long, because then the perimeter is exactly 20 meters, and for the sake of example, we want to run the running light around the room in the stucco or cornice below the ceiling.
So let’s see how the consumption of the 2×10 meter configurations develops with the LEDmaster controller in running light mode. The consumption for the 60 LEDs per meter is 40, 67, and 75 Watts for 10 meters powered from one end, both ends, and both ends plus the middle, respectively. In contrast, the consumption for the 30 LEDs per meter is 46, 57, and 58 Watts.
What does this show?
If the goal is the strongest colored light, then of course you should choose the one with 60 LEDs per meter, and with power connections every 5 meters. This means creating power connection points at 4 places under the ceiling, in both directions, so each of the 4 five-meter strips needs power cables at both ends. If we skimp on the implementation, thinking that the 67 Watts of light is enough, with only 2 connection points for the 4 ends, we’re mistaken. The strips will light up just as strongly at the connection points as our 75 Watt system would, but in the middle of the 10-meter sections, i.e., at the two 5-meter points, they will light up as if it were a 59 Watt system, resulting in a 21% difference in brightness every 5 meters. Therefore, it’s not worth saving on the 4 exit points and 8 connections.
On the other hand, if we choose the system with 30 LEDs per meter, our system will initially be only 58 Watts, but if we economize and have only 2 connection points at the 2 ends of the two 10-meter sections, we’ll do well. At the connection points, the strip will light up just as strongly as our 58 Watt system, while in the middle of the 10-meter sections, i.e., at the two 5-meter points, it will light up as if it were a 56 Watt system, since the measured 57 Watts is the average. It is easy to see that in this way, we will have only a 3.5% difference in brightness every 5 meters, which we are unlikely to notice. Therefore, it is worth saving on the 4 exit points and 8 connections for this strip, reducing them to 2 exit points and 4 connections.
Sharp-minded readers might say that the same applies if we create power connections at both ends every 2.5 meters instead of every 5 meters. Yes, the higher the power of an LED strip, the smaller the strip’s cross-section, and the lower the operating voltage, the shorter sections we need to create for uniform brightness. I usually say, you buy the strip, unroll it, assemble the system but don’t stick it up, just power it, hold it where you would stick it, and see if you like it. If you see that the middle is dimmer, then cut it in the middle and create a power connection there too.
| Consumption values calculated without power supply | Powered only from the controller | Powered only from one end of the strip | Powered from both ends of the strip | Powered from both ends and in the middle at 5 meters | |
| Ledmaster RF remote control + Bluetooth DRGB controller | |||||
| 1×5 meter LEDmaster 300 LED strip | with fixed white light | 15.1 | 15.0 | 16.3 | |
| with rainbow running light | 17.7 | 17.7 | 19.7 | ||
| 2×5 meter LEDmaster 300 LED strip | with fixed white light | 29.4 | 29.6 | 31.8 | |
| with rainbow running light | 34.6 | 35.1 | 38.6 | ||
| 2×10 meter LEDmaster 600 LED strip | with fixed white light | 33.2 | 35.5 | 53.9 | 56.4 |
| with rainbow running light | 39.2 | 39.8 | 67.3 | 74.6 | |
| SP511E IR remote control + Wi-fi DRGB controller | |||||
| 1×5 meter LEDmaster 300 LED strip | with fixed white light | 27.7 | 27.4 | 36.6 | |
| with rainbow running light | 13.2 | 13.2 | 14.2 | ||
| 2×5 meter LEDmaster 300 LED strip | with fixed white light | 54.1 | 54.2 | 62.3 | |
| with rainbow running light | 25.9 | 25.8 | 26.7 | ||
| 2×10 meter LEDmaster 600 LED strip | with fixed white light | 57.1 | 57.1 | 102.1 | 141.8 |
| with rainbow running light | 33.6 | 33.8 | 50.7 | 54.4 | |
| Ledmaster RF remote control + Bluetooth DRGB controller | |||||
| 1×5 meter Optonica 150 LED strip | with fixed white light | 11.7 | 11.7 | 11.6 | |
| with rainbow running light | 15.2 | 15.0 | 14.6 | ||
| 2×5 meter Optonica 150 LED strip | with fixed white light | 22.8 | 22.8 | 23.8 | |
| with rainbow running light | 29.8 | 29.2 | 29.4 | ||
| 2×10 meter Optonica 300 LED strip | with fixed white light | 38.4 | 38.8 | 44.9 | 44.7 |
| with rainbow running light | 45.8 | 46.1 | 57.4 | 57.6 | |
| SP511E IR remote control + Wi-fi DRGB controller | |||||
| 1×5 meter Optonica 150 LED strip | with fixed white light | 28.0 | 27.7 | 27.8 | |
| with rainbow running light | 10.9 | 10.9 | 10.5 | ||
| 2×5 meter Optonica 150 LED strip | with fixed white light | 54.8 | 54.1 | 55.9 | |
| with rainbow running light | 21.1 | 20.4 | 20.8 | ||
| 2×10 meter Optonica 300 LED strip | with fixed white light | 69.0 | 66.8 | 73.1 | 74.2 |
| with rainbow running light | 37.3 | 36.5 | 40.5 | 41.8 | |
I am publishing the following table just because if we think in terms of a complete system, we should consider its total energy consumption, including the power supply consumption. Naturally, if we operate these systems with a less efficient power supply, the consumption will be higher, but the light will not be.
| Consumption values, measured with a 150 Watt power supply with 87% efficiency | Powered only from the controller | Powered only from one end of the strip | Powered from both ends of the strip | Powered from both ends and the middle | |
| Ledmaster RF remote control + Bluetooth DRGB controller | |||||
| 1×5 meter LEDmaster 300 LED strip | with fixed white light | 17.3 | 17.2 | 18.7 | |
| with rainbow running light | 20.3 | 20.3 | 22.6 | ||
| 2×5 meter LEDmaster 300 LED strip | with fixed white light | 33.8 | 34.0 | 36.5 | |
| with rainbow running light | 39.8 | 40.4 | 44.4 | ||
| 2×10 meter LEDmaster 600 LED strip | with fixed white light | 38.2 | 40.8 | 61.9 | 64.8 |
| with rainbow running light | 45.0 | 45.8 | 77.4 | 85.7 | |
| SP511E IR remote control + Wi-fi DRGB controller | |||||
| 1×5 meter LEDmaster 300 LED strip | with fixed white light | 31.8 | 31.5 | 42.1 | |
| with rainbow running light | 15.2 | 15.2 | 16.3 | ||
| 2×5 meter LEDmaster 300 LED strip | with fixed white light | 62.2 | 62.3 | 71.6 | |
| with rainbow running light | 29.8 | 29.6 | 30.7 | ||
| 2×10 meter LEDmaster 600 LED strip | with fixed white light | 65.6 | 65.6 | 117.4 | 163.0 |
| with rainbow running light | 38.6 | 38.8 | 58.3 | 62.5 | |
| Ledmaster RF remote control + Bluetooth DRGB controller | |||||
| 1×5 meter Optonica 150 LED strip | with fixed white light | 13.5 | 13.4 | 13.3 | |
| with rainbow running light | 17.5 | 17.2 | 16.8 | ||
| 2×5 meter Optonica 150 LED strip | with fixed white light | 26.2 | 26.2 | 27.3 | |
| with rainbow running light | 34.2 | 33.6 | 33.8 | ||
| 2×10 meter Optonica 300 LED strip | with fixed white light | 44.1 | 44.6 | 51.6 | 51.4 |
| with rainbow running light | 52.7 | 53.0 | 66.0 | 66.2 | |
| SP511E IR remote control + Wi-fi DRGB controller | |||||
| 1×5 meter Optonica 150 LED strip | with fixed white light | 32.2 | 31.8 | 32.0 | |
| with rainbow running light | 12.5 | 12.5 | 12.1 | ||
| 2×5 meter Optonica 150 LED strip | with fixed white light | 63.0 | 62.2 | 64.3 | |
| with rainbow running light | 24.2 | 23.4 | 23.9 | ||
| 2×10 meter Optonica 300 LED strip | with fixed white light | 79.3 | 76.8 | 84.0 | 85.3 |
| with rainbow running light | 42.9 | 42.0 | 46.6 | 48.0 | |
The same applies to digital LED strips: due to the resistance of the LED strip, LEDs further from the connection point will light up weaker. The required frequency of power connections depends on the power of the given strip, operating voltage, strip cross-section, LED density (etc.), and our visual requirements. Generally, for 12 Volt strips with 60 LEDs per meter, connections at both ends of 5-meter rolls may be sufficient, while for those with 30 LEDs per meter, 10-meter sections can be formed.
Moreover, an interesting characteristic of DRGB LED strips is that when set to white light, which is cool white in RGB, the greater the voltage drop due to the strip’s resistance, the LEDs farther from the connection point will change from cool white to progressively yellower, and may even turn red. Although this effect is more prominent with 5 Volt DRGB LED strips, as lower voltage results in greater loss, and since the forward voltage of red LEDs is lower than that of blue or green, the voltage can drop so low along the strip that only the red LEDs remain operational.
Attention! I was talking about power connections, not the digital signal connections. The digital signal (usually the green wire) can only be connected to one end of a light strip, from the marked starting arrow. It will not work otherwise.