Samsung Horticulture LEDs
The first Samsung LEDs built on large area LED boards for plant lamps were the LM561C. Equipped with the new flip-chip technology, the successor LM301B was able to increase the efficiency levels for white LEDs once again, thus finally heralding the triumphant advance of mid-power LEDs in the horticulture sector.
With the growing popularity of Samsung's LED products among growers, it is no wonder that the company is trying to further develop this market. This was first indicated when Samsung published the PPF values for LM301B (more on this later). From then on it didn't take long - and the semiconductor manufacturer from South Korea announced its own horticulture version of the LM301 design in spring 2019.
But now comes the exciting question: LM301H vs LM301B - which LED is better for plant lamps?
LM301H - This is what the manufacturer advertises:
- Photosynthetic photon efficiency of 3.10 µmol/J at 65 mA (applies to the cold white 5000K version)
- Anti-sulfur coating
According to the data sheet, the LM301H LED has the same electrical and optical characteristics as the LM301B variant. It is available in different colour temperatures from 2200K to 6500K and in colour rendering index CRI 70-90.
Another variant with the designation LM301H One is now also available.
The About the LM301H One are rather average:
- Photosynthetic photon efficiency of 2,75 µmol/J at 65 m
- Single package solution for leafy vegetables
This special variant has a modified spectrum, which we will analyse in more detail in another article. Noticeable is the low power in the blue range, while the green-yellowish to red spectrum is more strongly weighted. According to Samsung, this should make it possible to grow lettuce well. However, the efficiency is disappointing, which doesn't do justice to the LM301 series.
LM301H vs. LM301B: a question of efficiency?
Since Samsung announced the new LED called LM301H, rumors and speculation have been spreading about the new product. In the DIY LED community there are more and more voices claiming that the new model is merely a label change. They say that the chips with the "H" are basically the same as those with the "B".
There is indeed much to suggest that For example, there is no significant difference to be seen in the data sheets of the two LM301 variants. A glance at Samsung's press releases nevertheless raised hope that the technology of the Horticulture version contains a fundamental innovation. Or is it just a listing of plant lighting specifications and a sulphur-resistant coating?
Official Samsung statements point to higher efficiency
After Samsung recognized that its LEDs for plant lighting are very competitive, the PPF / PPE values for the "normal" flagship, the LM301B, will first be released in 2018. The stated 2.92 µmol/J are impressive!
Samsung LM301B vs. LM301H under test
How did this increase of 6% come about? For an objective comparison, extensive measurements in an integrating sphere are necessary. However, a simple PPFD test can already provide a small clue and fortunately we are able to do this ourselves.
With the Apogee SQ-520 PPFD sensor and a small box, we wanted to compare the different Samsung LEDs under the most reproducible conditions possible.
In the first generation FLUXengine, the proven LM301B are installed, while from 2020 we will be using the FLUXengine v2 on the new LM301H.
In the comparison we simply let the first generation of the FLUXengine compete against the FLUXengine v2: 140x LM301B against 140x LM301H.
Advantage for the newcomers?
In fact, a lead of the FLUXengine v2 could be determined in the test.
With a current of 1000 mA the sensor of the FLUXengine showed 667 µmol, while the display of the FLUXengine v2 even showed 698 µmol. In addition, the FLUXengine with LM301B dropped a little more voltage, so that the bottom line was a higher efficiency of almost 5%.
The sorting makes the difference
However, this 5%ige difference is not necessarily due to the better LM301H. The first generation FLUXengines were equipped with unsorted LM301B. For the successor we decided to use the higher quality SL-Bin sorting. The difference corresponds almost exactly to the measured 5 %s! The "average" SK Bin delivers an average of 37 lm at 65 mA, while the SL Bin delivers an average of 39 lm (unfortunately only lumen values are given).
Which Samsung LED chip is better suited for grow LEDs?
We could only measure with simple test equipment, so the results are subject to various uncertainties. At first glance, however, it is still not possible to confirm that the LM301H is the better choice for grow LEDs.
The difference between our LM301B and LM301H is probably due to the stricter sorting and not to any particular innovation by Samsung. How the contradictory press releases come about remains a mystery.
But there is one good thing we can gain from this: It has been confirmed that the LM301H SL Bin are extremely efficient LEDs, which in this case even surpassed the very good LM301B.
The bottom line is that when comparing Samsung LEDs, it makes more sense to look for the highest possible bin than for the suffix -H or -B. In other words: LM301H and LM301B = both super! SL Bin = even better!