Dimmable 100W LED Grow Light

With a **90-degree beam angle**, the manufacturer's claim of **557 μmol/m²/s PPFD at 30cm over 1m²** with only **150 μmol/s PPF** is **definitely incorrect**—here's the breakdown:

---

### **Why It’s Impossible**
1. **Beam Angle Physics**
- A **90-degree beam angle** at **30cm height** creates a **~60cm × 60cm coverage area** (0.36 m²), **not 1m²**.
- **At 1m²**, the light would be **far less concentrated** (PPFD drops significantly).
- To cover **1m² evenly**, the light would need to be **raised higher**, reducing PPFD further.

2. **PPF vs. PPFD Calculation**
- Even if **all 150 μmol/s** were perfectly concentrated into **0.36 m²**:
\[
\text{PPFD} = \frac{150 \, \mu mol/s}{0.36 \, m²} ≈ 417 \, \mu mol/m²/s \, \text{(theoretical max)}
\]
- **557 μmol/m²/s would require 200 μmol/s PPF** for the same area:
\[
557 \times 0.36 ≈ 200 \, \mu mol/s
\]
- Your light only emits **150 μmol/s**, making **557 PPFD impossible even in the hotspot**.

3. **Real-World PPFD Distribution**
- LEDs with **90° optics** don’t have a perfectly uniform beam.
- **Typical PPFD distribution**:
- **Center (hotspot)**: ~400 μmol/m²/s (best-case, still below 557).
- **Edges (1m²)**: <100 μmol/m²/s.
- **Average PPFD over 1m²**: Likely **under 150 μmol/m²/s**.

---

### **What’s Really Going On?**
- **Misleading PPFD Claim**: The manufacturer is likely reporting a **peak center measurement** (not average over 1m²).
- **Incorrect Testing Conditions**: They might have:
- Measured **closer than 30cm** (e.g., 15cm).
- Used **reflective walls** to artificially boost PPFD.
- Confused **µmol/m²/s (PPFD)** with **µmol/s (PPF)** in specs.

---

### **What Should You Trust?**
1. **For a 100W LED with 90° Beam Angle**:
- **Realistic PPFD at 30cm**:
- **Hotspot (0.25–0.5m²)**: 300–400 μmol/m²/s.
- **1m² average**: 100–200 μmol/m²/s.
- **Efficiency Check**: 150 PPF for 100W is **low (1.5 µmol/J)**. Modern lights hit **2.5+ µmol/J** (e.g., 250+ PPF for 100W).

2. **Ask the Manufacturer For**:
- A **PPFD map** (not just one number).
- **Test conditions** (distance, area, reflectors).

---

### **Final Verdict**
The claimed **557 PPFD at 30cm over 1m²** is **physically impossible** with:
- **150 PPF total output**,
- **90° beam angle**.

**Either:**
- The **PPFD is a hotspot reading** (not 1m² average),
- The **PPF is underreported**, or
- The **specs are false/misleading**.

**Recommendation:**
- **Reject this light** if the specs aren’t transparent.
- Look for **verified PPFD maps** (e.g., Spider Farmer, Mars Hydro, HLG).

Need help finding a legit light? Share your grow space size/goals, and I’ll suggest alternatives!

Great Light! Happy plans

Nice unit totally protected from humidity long cables. Dimmable- good idea since the out put is high. I will probably get to of the 75 watt units. For the price you get decent more output compared to buying the equivalent in bulbs.
There's a reason why I use Sansi fixtures- consistently, service, and warranty.

Plant was a little unhappy with me. But we hooked this up above it, I run it 10 hours a day. Three new sprouts within a week. Would buy again.

Great great light for the money. The plants are flourishing underneath the warmth of its brightness. A+++