I often use a 1.25 multiplier (extra 25%) when sizing LED Drivers, but its only necessary if the required Max Output is uncertain, it adds some redundancy. The most efficient operating range for LED Drivers appears to be ~ 85 - 90%, so yes the LED Drivers could be slightly oversized, if desired.
A simple procedure to Size a Grow Light for any "Small" Grow Area is;
Grow Light Sizing; Imperial and Metric Preliminary: Part A
1. Get the Grow area in square feet or square meters (note1).
[2 ft x 4 ft = 8 sq ft]
[68 cm x 120 cm = 0.8 sq m]
2. Select the required Intensity (note2).
a. 20 PPF/sq ft or 200 PPF/sq m = Seedlings and Cuttings
b. 40 PPF/sq ft or 400 PPF/sq m = Vegetative
c. 60 PPF/sq ft or 600 PPF/sq m = Flowering and Late Vegetative
d. 80 PPF/sq ft or 800 PPF/sq m = Flowering, CO2 Enhanced
e. 100 PPF/sq ft or 1000 PPF/sq m = Flowering, CO2 Enhanced, Controlled Environment
3. Multiply Area by required Intensity to get required Fixture size;
[8 (sq ft) x 80 (PPF / sq ft) = 640 PPF fixture]
[0.8 (sq m) x 800 (PPFD) = 640 PPF Fixture]
4. Get an approximate Fixture Watts by dividing Fixture PPF by an "average" LED Strip PPE (note3)
[640 (Watts) / 2.5 (PPE) = 256 Watts]
Notes: 1. 10 sq ft = ~ 1 sq m ( = 0.93 m2) 2. PPF = umol/s and PPF/sq m = PPFD (umol/s/m2) 3. PPE = umol/s/W and 2.5 PPE is a nominally efficient LED.
Grow Light Sizing; LED Strip and Driver Selection: Part B
5. LED Strip Selection requires the Strip's; Lumens, Lm/W, Vf, Amps, Watts (Vf x Amps)
[1120mm BXEB Gen2 3500K; 4780 Lm, 175 Lm/W, 39 Vf, 0.700 A, 27.3 W]
6. The LED Strip's Lumens and Lumens/Watt can be converted to PPF and PPE (note4);
[4780 (Lm) x 0.015 (PPF/Lm) = 71.7 PPF (umol/s) each]
[175 (Lm/W) x 0.015 (PPF/Lm) = 2.625 PPE (PPF/W)]
7. Use the preliminary req'd PPF (from Part A) to Calculate the quantity of req'd Strips
[640 (PPF) / 71.7 (PPF/strip) = 8.92 Strips]
8. Use the req'd Strip quantity, Watts and Vf (Forward Volts) to Calculate the req'd LED Driver Specs
[9 (Strips) x 27.3 (Watts) = 245.7 Watts & 39 Vf]
9. Use the req'd Driver Watts and a reserve of ~ 25% (1.25 Factor) to Select an LED Driver(note5)
[245.7 (Watts) x 1.25 = 307 Watts & 39 Vf]
Notes: 1. 10 sq ft = ~ 1 sq m ( = 0.93 m2) 2. PPF = umol/s and PPF/sq m = PPFD (umol/s/m2) 3. PPE = umol/s/W and 2.5 PPE is a nominally efficient LED. 4. Conversion Factor = 0.015 PPF/Lm for 3000K to 5000K, 80CRI LED... https://www.biorxiv.org/content/biorxiv ... 0.full.pdf 5. The Reserve factor of ~ 25% allows for an increase of PPF, if required.
The push-in connectors work well but are "Permanent" and not designed to be removed / adjusted like the lever-lock types...
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