String Inverters vs Micro Inverters — What’s the Real Difference?
Most rooftop solar in India uses a string inverter — one central box that converts DC from all panels to AC at once. It’s simple and cost-effective. But it has a fundamental flaw: every panel in the string must perform at the same level. Shade one panel, a tree limb crosses one corner, bird droppings land on one module — the entire string drops to match the weakest panel.
A micro inverter solves this at the source. Instead of one central inverter, each solar panel gets its own small inverter mounted directly behind it. Each panel operates with its own MPPT (Maximum Power Point Tracking). Shading one panel has zero effect on the others.
Watch: Hoymiles Micro Inverters Explained in Kannada
ಕನ್ನಡದಲ್ಲಿ ವಿವರಣೆ: Hoymiles ಮೈಕ್ರೋ ಇನ್ವರ್ಟರ್ ಹೇಗೆ ಕೆಲಸ ಮಾಡುತ್ತದೆ, ಸ್ಥಾಪನೆ ಪ್ರಕ್ರಿಯೆ, ಮತ್ತು ಭಾರತೀಯ ಛಾವಣಿಗಳಿಗೆ ಏಕೆ ಸೂಕ್ತ.
Why Micro Inverters Make Sense for Indian Rooftops
Indian homes face conditions that string inverters struggle with:
Mixed orientations — Many homes have roof sections facing different directions: east, west, flat, sloped. A string inverter cannot optimise across orientations simultaneously. With micro inverters, an east-facing panel and a west-facing panel each run at their own maximum — the east panel captures morning sun; the west panel captures evening sun. Total daily yield goes up.
Partial shading — Trees, water tanks, staircase structures, neighbouring buildings. Most urban and peri-urban rooftops in India have some shade for at least part of the day. With a string inverter, a shadow on one panel can reduce output by 30–50% system-wide at peak times. With micro inverters, only the shaded panel underperforms.
Long-term mismatch — As panels age at different rates, soiling accumulates unevenly, and string losses compound over 10–25 years. Micro inverters eliminate this: each panel always runs at its own MPPT regardless of what others are doing.
Expandability — Adding panels to a string system later requires string recalculation and may exceed the inverter’s capacity. With micro inverters, you add one panel and one micro inverter at a time — no redesign, no constraint.
Hoymiles HM and HMS Series — What Techedge Supplies
Techedge is an authorised Hoymiles dealer in Bengaluru, supplying two series:
HM Series — Cost-Effective Per-Panel MPPT
300 W to 2000 W output, 1 to 4 PV inputs depending on model. The HM-600, HM-700 and HM-800 are the most popular for residential use — two panels per micro inverter. The HM-1500 and HM-2000 handle four panels each.
- Max efficiency: 96.7% | EU efficiency: 95.8%
- IP67 weatherproof — tested for Indian monsoon conditions
- 12-year warranty
- Monitoring: Hoymiles DTU + S-Miles Cloud app
HMS Series — Next-Generation Performance
800 W to 2000 W output, 2 to 4 PV inputs. The HMS series offers measurably better efficiency and a longer warranty — the right choice for premium residential and small commercial installations.
- Max efficiency: 97.0% | EU efficiency: 96.2%
- IP67, 15-year warranty
- Higher thermal performance at elevated operating temperatures
Both series connect to your 230 V / 50 Hz grid. DC wiring stays short — just from panel to the micro inverter behind it. No long DC cable runs across the roof. No central inverter box on the wall.
Module-Level Monitoring: See Every Panel in Real Time
Every Hoymiles micro inverter connects to the DTU (Data Transfer Unit) gateway, which feeds the S-Miles Cloud app. You see:
- Live watt output from each individual panel
- Generation history per panel, per day and per month
- Fault alerts per panel — not just “system stopped”
- Lifetime energy generated and CO₂ saved
A string inverter tells you total system output. A micro inverter system tells you exactly which panel is underperforming and by how much. For a rooftop you’re counting on for 25 years, that visibility matters.
Is a Micro Inverter Right for Your Rooftop?
A micro inverter system is the right choice when:
- Your rooftop has shading from trees, water tanks, parapet walls or neighbouring structures
- You have panels on multiple roof faces (east + west, flat + sloped sections)
- You want to expand the system in phases — start with 4 panels, add 2 more next year
- You want per-panel fault isolation (one unit fails, the rest keep running)
- You value a longer-warranty, lower-maintenance premium system
A string inverter may be the better choice when:
- Your rooftop is completely unshaded, single orientation — a well-designed string system is highly efficient in this case
- You need a large system above 15–20 kW where commercial-grade string inverters are more cost-effective
- Upfront cost is the primary constraint
Pricing and Supply from Techedge, Bengaluru
Techedge stocks and supplies Hoymiles HM and HMS series micro inverters across Bengaluru and Karnataka. Indicative prices (excluding 12% GST):
| Model | Output | PV Inputs | Price |
|---|---|---|---|
| HM-600 | 600 W | 2 | ₹5,800 |
| HM-800 | 800 W | 2 | ₹6,800 |
| HM-1000 | 1000 W | 2 | ₹8,200 |
| HMS-800W-T2 | 800 W | 2 | ₹7,500 |
| HMS-1000W-T2 | 1000 W | 2 | ₹9,000 |
For complete system pricing — micro inverters, DTU gateway, panels, mounting, and installation — contact our engineering team for a site-specific design.